Old lady swallowed a fly

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Task
Old lady swallowed a fly
You are encouraged to solve this task according to the task description, using any language you may know.
Task

Present a program which emits the lyrics to the song   I Knew an Old Lady Who Swallowed a Fly,   taking advantage of the repetitive structure of the song's lyrics.

This song has multiple versions with slightly different lyrics, so all these programs might not emit identical output.


Other tasks related to string operations:
Metrics
Counting
Remove/replace
Anagrams/Derangements/shuffling
Find/Search/Determine
Formatting
Song lyrics/poems/Mad Libs/phrases
Tokenize
Sequences



11l

Translation of: Python
V animals = [
        (‘fly’, ‘I don't know why she swallowed a fly, perhaps she'll die.’),
        (‘spider’, ‘It wiggled and jiggled and tickled inside her.’),
        (‘bird’, ‘How absurd, to swallow a bird.’),
        (‘cat’, ‘Imagine that, she swallowed a cat.’),
        (‘dog’, ‘What a hog, to swallow a dog.’),
        (‘goat’, ‘She just opened her throat and swallowed a goat.’),
        (‘cow’, ‘I don't know how she swallowed a cow.’),
        (‘horse’, ‘She's dead, of course.’)]

L(animal_lyric) animals
   V i = L.index
   V (animal, lyric) = animal_lyric
   print("There was an old lady who swallowed a #..\n#.".format(animal, lyric))

   I animal == ‘horse’
      L.break

   L(predator, prey) zip(animals[(i .< 0).step(-1)], animals[(i - 1 ..).step(-1)])
      print("\tShe swallowed the #. to catch the #.".format(predator[0], prey[0]))

   I animal != ‘fly’
      print(animals[0][1])
   print()

8080 Assembly

	org	100h
	mvi	c,-1	; C = verse counter
verse:	inr 	c
	lxi	d,lady	; There was an old lady who swallowed a ...
	call	prstr
	mov	e,c	; <animal>
	call	pbeast
	lxi	d,comma
	call	prstr
	mov	e,c	; verse
	call	pverse
	mov	a,c	; is this the first verse?
	ana	a
	jz	verse	; then we're not swallowing animals yet
	cpi	7	; otherwise, is the lady dead yet?
	rz		; if so, stop.
	mov	b,c	; otherwise, start swallowing
swallo:	lxi	d,swlw1	; She swallowed the 
	call	prstr
	mov	e,b	; <current animal>
	call	pbeast
	lxi	d,swlw2	; to catch the
	call	prstr
	dcr	b
	push	psw	; store state (is B zero now)
	mov	e,b	; <previous animal>
	call	pbeast
	lxi	d,comma
	call 	prstr
	mov	a,b
	cpi	2
	mov	e,b	; print associated verse if < 2
	cc	pverse
	pop	psw	; was B zero?
	jnz	swallo	; if not, swallow more
	jmp	verse	; if so, next verse 
prstr:	push	b	; print string in DE
	mvi	c,9	
	call 	5
	pop 	b
	ret
pverse:	lxi	h,verses
	jmp	pstrn
pbeast:	lxi	h,beasts
	;;;	Print the E'th string from the list at HL
pstrn:	push	b	; keep counters in B and C
	mvi	a,'$'	; end-of-string marker
	inr	e
pscan:	cmp	m	; keep going until we find one
	inx	h
	jnz	pscan
	dcr	e	; is this the one we wanted?
	jnz	pscan	; if not, keep going
	xchg		; otherwise, put in DE
	mvi	c,9	; print string using CP/M
	call	5
	pop	b	; restore counters
	ret
lady:	db	'There was an old lady who swallowed a '
beasts:	db	'$fly$spider$bird$cat$dog$goat$cow$horse'
verses:	db	'$I don',39,'t know why she swallowed that fly -'
	db	' Perhaps she',39,'ll die.',13,10,13,10
	db	'$That wiggled and jiggled and tickled inside her!',13,10
	db	'$How absurd to swallow a bird',13,10
	db	'$Imagine that! She swallowed a cat!',13,10
	db	'$What a hog to swallow a dog',13,10
	db	'$She just opened her throat and swallowed that goat',13,10
	db	'$I don',39,'t know how she swallowed that cow',13,10
	db	'$She',39,'s dead, of course.',13,10,'$'
swlw1:	db	'She swallowed the $'
swlw2:	db	' to catch the $'
comma:	db	',',13,10,'$'

8086 Assembly

	cpu	8086
	org	100h
section	.text
	mov	bl,-1		; BL = verse counter
verse:	inc	bl
	mov	dx,lady		; There was an old lady who swallowed
	call	prstr
	mov	dl,bl		; <animal>
	call	pbeast
	mov	dx,comma
	call	prstr
	mov	dl,bl		; verse
	call	pverse
	test	bl,bl		; is this the first verse?
	jz	verse		; then we're not swallowing anything yet
	cmp	bl,7		; otherwise, is the lady dead yet?
	je	stop		; if so, stop.
	mov	bh,bl		; otherwise, start swallowing
swallo:	mov	dx,swlw1	; She swallowed the
	call	prstr
	mov	dl,bh		; <current animal>
	call	pbeast
	mov	dx,swlw2	; to catch the
	call	prstr
	dec	bh		; <previous animal>
	mov	dl,bh
	call 	pbeast
	mov	dx,comma
	call	prstr
	cmp	bh,2		; print associated verse if BH<2
	jae	.next
	mov	dl,bh
	call	pverse
.next:	test	bh,bh		; is BH zero yet?
	jnz	swallo		; if not, swallow next animal
	jmp	verse		; otherwise, print next verse
pverse:	mov	di,verses	; Print verse DL
	jmp	pstrn
pbeast:	mov	di,beasts	; Print animal DL 
	;;;	Print DL'th string from [DI]
pstrn:	inc	dl
	mov	al,'$'		; end-of-string marker
.scan:	mov	cx,-1
	repne	scasb
	dec	dl
	jnz	.scan
	mov	dx,di
prstr:	mov	ah,9		; MS-DOS syscall to print a string
	int	21h
stop:	ret
section	.data
lady:	db	'There was an old lady who swallowed a '
beasts:	db	'$fly$spider$bird$cat$dog$goat$cow$horse'
verses:	db	'$I don',39,'t know why she swallowed that fly -'
	db	' Perhaps she',39,'ll die.',13,10,13,10
	db	'$That wiggled and jiggled and tickled inside her!',13,10
	db	'$How absurd to swallow a bird',13,10
	db	'$Imagine that! She swallowed a cat!',13,10
	db	'$What a hog to swallow a dog',13,10
	db	'$She just opened her throat and swallowed that goat',13,10
	db	'$I don',39,'t know how she swallowed that cow',13,10
	db	'$She',39,'s dead, of course.',13,10,'$'
swlw1:	db	'She swallowed the $'
swlw2:	db	' to catch the $'
comma:	db	',',13,10,'$'

Ada

with Ada.Text_IO, Ada.Containers.Indefinite_Doubly_Linked_Lists; use Ada.Text_IO;

procedure Swallow_Fly is

   package Strings is new Ada.Containers.Indefinite_Doubly_Linked_Lists(String);

   Lines, Animals: Strings.List;

   procedure Swallow(Animal: String;
                     Second_Line: String;
                     Permanent_Second_Line: Boolean := True) is

      procedure Print(C: Strings.Cursor) is
      begin
         Put_Line(Strings.Element(C));
      end Print;

   begin
      Put_Line("There was an old lady who swallowed a " & Animal & ",");
      Put_Line(Second_Line);
      if not Animals.Is_Empty then
         Lines.Prepend("She swallowed the " & Animal & " to catch the " &
			 Animals.Last_Element & ",");
      end if;
      Lines.Iterate(Print'Access);
      New_Line;
      if Permanent_Second_Line then
         Lines.Prepend(Second_Line);
      end if;
      Animals.Append(Animal); -- you need "to catch the " most recent animal
   end Swallow;

   procedure Swallow_TSA(Animal: String; Part_Of_Line_2: String) is
   begin
      Swallow(Animal, Part_Of_Line_2 &", to swallow a " & Animal & ";", False);
   end Swallow_TSA;

   procedure Swallow_SSA(Animal: String; Part_Of_Line_2: String) is
   begin
      Swallow(Animal, Part_Of_Line_2 &" she swallowed a " & Animal & ";", False);
   end Swallow_SSA;

begin
   Lines.Append("Perhaps she'll die!");

   Swallow("fly", "But I don't know why she swallowed the fly,");
   Swallow("spider",  "That wriggled and jiggled and tickled inside her;");
   Swallow_TSA("bird", "Quite absurd");
   Swallow_TSA("cat", "Fancy that");
   Swallow_TSA("dog", "What a hog");
   Swallow_TSA("pig", "Her mouth was so big");
   Swallow_TSA("goat","She just opened her throat");
   Swallow_SSA("cow", "I don't know how");
   Swallow_TSA("donkey", "It was rather wonky");

   Put_Line("There was an old lady who swallowed a horse ...");
   Put_Line("She's dead, of course!");
end Swallow_Fly;

ALGOL 68

Using Logic

Works with: ALGOL 68 version Revision 1 - no extensions to language used.
Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny.
#!/usr/local/bin/a68g --script #

STRING sw=" swallow ",swd=sw[:UPB sw-1]+"ed ", tsa=". To"+sw+"a";

INT count prev := 0; [9]STRING prev;

PROC vs = (STRING in wot,[]STRING co)VOID: (
  STRING wot = " "+in wot;
  printf(($g$,"I know an old lady who",swd,"a",wot,".",$l$));
  IF UPB co = 1 THEN
    printf(($gl$,co))
  ELIF UPB co > 1 THEN
    printf(($g$,co,wot+".",$l$))
  FI;
  IF count prev NE UPB prev THEN
    prev[count prev+:=1]:=wot;
    FOR i FROM count prev BY -1 TO 2 DO
      printf(($gl$,"She"+swd+"the"+prev[i]+" to catch the"+prev[i-1]+"."))
    OD;
    printf(($gl$,"I don't know why she"+swd+"the fly.",
                 "Perhaps she'll die.", $l$))
  FI
);

vs("fly",());
vs("spider","That wriggled and jiggled and tickled inside her.");
vs("Bird",("Quite absurd",tsa));
vs("Cat",("Fancy that",tsa));
vs("Dog",("What a hog",tsa));
vs("Pig",("Her mouth was so big",tsa));
vs("Goat",("She just opened her throat",tsa));
vs("Cow",("I don't know how",tsa));
vs("Donkey",("It was rather wonky",tsa));
vs("Horse","She's dead, of course!")

Using a dictionary

Works with: ALGOL 68 version Revision 1 - no extensions to language used.
Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny.
#!/usr/local/bin/a68g --script #

STRING a="WBXAY",b="WCXBY",c="WDXCY",d="WEXDY",
       e="WFXEY",f="WGXFY",g="WHXGY",h="WIXHY",
       k="K",z="Z",l="";

[]STRING
  w=( # Assuming ASCII ordering #
    "fly","spider","Bird","Cat","Dog","Pig","Goat","Cow","Donkey","Horse",

    "I don't know why she swallowed the fly.",
    "That wriggled and jiggled and tickled inside her.",
    "Quite absurd","Fancy that","What a hog",
    "Her mouth was so big","She just opened her throat",
    "I don't know how","It was rather wonky",
    "She's dead, of course!",

    "I know an old lady who swallowed a ",
    ". To swallow a ",
    "She swallowed the "," to catch the ",".",
    "Perhaps she'll die."),
  v=(
    "UAY",k,z,l,
    "UBY","L",a,k,z,l,
    "UCY","MVCY",b,a,k,z,l,
    "UDY","NVDY",c,b,a,k,z,l,
    "UEY","OVEY",d,c,b,a,k,z,l,
    "UFY","PVFY",e,d,c,b,a,k,z,l,
    "UGY","QVGY",f,e,d,c,b,a,k,z,l,
    "UHY","RVHY",g,f,e,d,c,b,a,k,z,l,
    "UIY","SVIY",h,g,f,e,d,c,b,a,k,z,l,
    "UJY","T");

FOR i TO UPB v DO
  FOR j TO UPB v[i] DO
    print(w[ABS v[i][j] - ABS "A" + 1])
  OD;
  print(new line)
OD

APL

Works with: Dyalog APL
oldLady{
    N⎕TC[3]
    a'fly' 'spider' 'bird' 'cat' 'dog' 'goat' 'cow' 'horse'
    v'I don''t know why she swallowed that fly - Perhaps she''ll die',N
    vv,⊂'That wiggled and jiggled and tickled inside her!'
    vv,⊂'How absurd to swallow a bird'
    vv,⊂'Imagine that! She swallowed a cat!'
    vv,⊂'What a hog to swallow a dog'
    vv,⊂'She just opened her throat and swallowed that goat'
    vv,⊂'I don''t know how she swallowed that cow'
    vv,⊂'She''s dead, of course.'
    l'There was an old lady who swallowed a '
    {
        l,a[],N,v[],N,(<8)/{
            =0:''
            r'She swallowed the ',a[],' to catch the ',a[-1],N
            r,(3)/v[-1],N
        }¨1↓⍳
    }¨8
}

Applesoft BASIC

 100  FOR N = 0 TO 7: READ A$(N),E$(N): NEXT N:N = N - 1
 110  FOR C = 1 TO N
 120      PRINT M$M$"THERE WAS AN OLD LADY WHO SWALLOWED A "A$(C);
 130      LET M$ =  CHR$ (13)
 140      IF C > 1 THEN  PRINT M$E$(C);: IF C < N THEN  FOR B = C TO 2 STEP  - 1: PRINT M$A$(0)A$(B)" TO CATCH THE "A$(B - 1) MID$ (",;",1 + (B = 2),1);: NEXT B
 150      IF C < N THEN  PRINT M$E$(1)E$(0);
 160  NEXT C
 170  END
 200  DATA"  SHE SWALLOWED A "," - PERHAPS SHE'LL DIE!"
 210  DATA"FLY","I DON'T KNOW WHY SHE SWALLOWED A FLY"
 220  DATA"SPIDER","THAT WRIGGLED AND JIGGLED AND TICKLED INSIDE HER;"
 230  DATA"BIRD","HOW ABSURD TO SWALLOW A BIRD."
 240  DATA"CAT","FANCY THAT TO SWALLOW A CAT!"
 250  DATA"DOG","WHAT A HOG, TO SWALLOW A DOG;"
 260  DATA"COW","I DON'T KNOW HOW SHE SWALLOWED A COW,"
 270  DATA"HORSE","SHE'S DEAD, OF COURSE!"

ARM Assembly

.global _start
_start:	eor	r8,r8,r8	@ Verse counter
verse:	add	r8,r8,#1	@ Next verse
	ldr	r1,=lady	@ There was an old lady who swallowed...
	bl	pstr
	mov	r2,r8
	bl	pbeast		@ <an animal>
	ldr	r1,=comma
	bl	pstr
	mov	r2,r8
	bl	pverse		@ Print the corresponding verse
	cmp	r8,#1		@ First verse?
	beq	verse		@ Then we're not swallowing anything yet
	cmp	r8,#8		@ Otherwise, is the lady dead yet?
	moveq	r7,#1		@ If so, stop.	
	swieq	#0
	mov	r9,r8		@ Otherwise, start swallowing
swallo:	ldr	r1,=swa1	@ She swallowed the ...	
	bl	pstr
	mov	r2,r9		@ <current animal>
	bl	pbeast
	ldr	r1,=swa2	@ ...to catch the...
	bl	pstr
	sub	r9,r9,#1
	mov	r2,r9		@ <previous animal>
	bl	pbeast
	ldr	r1,=comma
	bl	pstr
	cmp	r9,#2		@ Print the associated verse for 2 and 1
	movle	r2,r9
	blle 	pverse
	cmp	r9,#1		@ Last animal?
	bgt	swallo		@ If not, keep swallowing
	b	verse		@ But if so, next verse
pverse:	ldr	r1,=verses	@ Print verse R2 
	b	pstrn
pbeast:	ldr	r1,=beasts	@ Print animal R2 
pstrn:	ldrb	r0,[r1],#1	@ R2'th string from R1 - get byte
	tst	r0,r0		@ Zero yet?
	bne	pstrn 		@ If not keep going
	subs	r2,r2,#1	@ Is this the right string?
	bne	pstrn		@ If not keep going
@ Print 0-terminated string starting at R1 using Linux.
pstr:	mov	r2,r1		@ Find end
1:	ldrb	r0,[r2],#1	@ Get current byte
	tst	r0,r0		@ Zero yet?
	bne	1b		@ If not keep scanning
	sub	r2,r2,r1	@ Calculate string length
	mov	r0,#1		@ 1 = Linux stdout
	mov	r7,#4		@ 4 = Linux write syscall
	push	{lr}		@ Keep link register
	swi 	#0		@ Do syscall 
	pop	{lr}		@ Restore link register
	bx	lr
lady:	.ascii	"There was an old lady who swallowed a "
beasts:	.ascii	"\0fly\0spider\0bird\0cat\0dog\0goat\0cow\0horse"
verses:	.ascii	"\0I don't know why she swallowed that fly - "
	.ascii	"Perhaps she'll die.\n\n"
	.ascii	"\0That wiggled and jiggled and tickled inside her!\n"
	.ascii	"\0How absurd to swallow a bird\n"
	.ascii	"\0Imagine that! She swallowed a cat!\n"
	.ascii	"\0What a hog to swallow a dog\n"
	.ascii	"\0She just opened her throat and swallowed that goat\n"
	.ascii	"\0I don't know how she swallowed that cow\n"
	.asciz	"\0She's dead, of course.\n"
swa1:	.asciz	"She swallowed the "
swa2:	.asciz	" to catch the "
comma:	.asciz	",\n"

AutoHotkey

Works with: AutoHotkey 1.1
Animals := [["fly",	"I don't know why she swallowed the "]
	  , ["spider",	"That wriggled and jiggled and tickled inside her"]
	  , ["bird",	"Quite absurd"]
	  , ["cat",	"Fancy that"]
	  , ["dog",	"What a hog"]
	  , ["pig",	"Her mouth was so big"]
	  , ["goat",	"She just opened her throat"]
	  , ["cow",	"I don't know how"]
	  , ["donkey",	"It was rather wonky"]
	  , ["horse",	"She's dead, of course!"]]

for i, V in Animals {
	Output .= "I know an old lady who swallowed a " V.1 ".`n"
	. (i = 1 ? Saved := V.2 V.1 ".`nPerhaps she'll die.`n`n"
	: V.2 (i = Animals.MaxIndex() ? "" : (i = 2 ? "" : ". To swallow a " V.1) ".`n" 
	. (Saved := "She swallowed the " V.1 " to catch the " Animals[i - 1].1 ".`n" Saved)))
}

MsgBox, % Output

AWK

# syntax: GAWK -f OLD_LADY_SWALLOWED_A_FLY.AWK
BEGIN {
    arr[++i] = "fly/"
    arr[++i] = "spider/That wriggled and jiggled and tickled inside her"
    arr[++i] = "bird/Quite absurd@"
    arr[++i] = "cat/Fancy that@"
    arr[++i] = "dog/What a hog@"
    arr[++i] = "pig/Her mouth was so big@"
    arr[++i] = "goat/Opened her throat and down went the goat"
    arr[++i] = "cow/I don't know how@"
    arr[++i] = "donkey/It was rather wonkey@"
    arr[++i] = "horse/She's dead of course"
    leng = i # array length
    for (i=1; i<=leng; i++) {
      s = arr[i]
      A[i] = substr(s,1,index(s,"/")-1) # critter name
      text = substr(s,index(s,"/")+1)
      sub(/@/," to swallow a "A[i],text)
      printf("I know an old lady who swallowed a %s.\n",A[i])
      if (text != "") {
        printf("%s.\n",text)
      }
      if (i == leng) {
        break
      }
      for (j=i; j>1; j--) {
        printf("She swallowed the %s to catch the %s.\n",A[j],A[j-1])
      }
      printf("I don't know why she swallowed the fly.\n")
      printf("Perhaps she'll die.\n\n")
    }
    exit(0)
}

Babel

((main {fly !})

(fly 
    {{"There was an old lady who swallowed a " <<
        iter 1 - dup
        <- 0 animal ! nl << ->
           1 animal !    <<
        {iter 10 ~=}{
            " " <<
            {iter 1 =}{last}{fnord} ifte
            iter 1 - 0 animal ! nl << 
                {"She swallowed the " <<
                this_iter ! 0 animal ! <<
                " to catch the " <<
                next_iter ! 0 animal ! nl <<
                {iter 2 =}
                    {8 1 animal ! nl <<}
                    {fnord}
                ifte}
            11 iter - 1 -
            times}
            {fnord}
        ifte
        "But I don't know why she swallowed the fly\nPerhaps she'll die\n\n" <<}
    animals len
    times})

(next_iter {10 iter - })
(this_iter {next_iter ! 1 -})

(animal { <- <- animals -> ith -> ith})

-- There are 10 animals
(animals 
   (("horse"    "She's dead of course...\n")
    ("donkey"   "It was rather wonkey! To swallow a")
    ("cow"      "I don't know how she swallowed a")
    ("goat"     "She just opened her throat! And swallowed the")
    ("pig"      "Her mouth was so big, to swallow a")
    ("dog"      "What a hog! To swallow a")
    ("cat"      "Fancy that! She swallowed a")
    ("bird"     "Quite absurd to swallow a")
    ("spider"   "That wriggled and jiggled and tickled inside her")
    ("fly"      " "))))

Batch File

@echo off
setlocal enabledelayedexpansion

	%== An "ugly" pseudo-array ===%
set pseudo=^
fly/@^
spider/That_wiggled_and_jiggled_and_tickled_inside_her,@^
bird/How_absurd,_to_swallow_a_bird,@^
cat/Imagine_that._She_swallowed_a_cat,@^
dog/What_a_hog_to_swallow_a_dog,@^
goat/She_just_opened_her_throat_and_swallowed_that_goat,@^
cow/I_don't_know_how_she_swallowed_that_cow,@^
horse/She's_dead_of_course...

	%== Counting and seperating... ===%
set str=!pseudo!
:count
if "!str!"=="" goto print_song
for /f "tokens=1,* delims=@" %%A in ("!str!") do (
	set /a cnt+=1
	for /f "tokens=1,2 delims=/" %%C in ("%%A") do (
		set animal!cnt!=%%C
		set comment!cnt!=%%D
	)
	set str=%%B
)
goto count

	%== Print the song ===%
:print_song
for /l %%i in (1,1,!cnt!) do (
	echo There was an old lady who swallowed a !animal%%i!.
	if not "!comment%%i!"=="" echo !comment%%i:_= !	
	if %%i equ !cnt! goto done

	for /l %%j in (%%i,-1,2) do (
		set/a prev=%%j-1
		call set prev_animal=%%animal!prev!%%
		echo She swallowed the !animal%%j! to catch the !prev_animal!.
	)
	echo I don't know why she swallowed the fly.
	echo Perhaps she'll die.
	echo.
)
:done
pause>nul&exit/b 0

BBC BASIC

This prints the lyrics from the Wikipedia page, more or less. I don't know anything about goats and donkeys and the like.

REM >oldlady
DIM swallowings$(6, 1)
swallowings$() = "fly", "+why", "spider", "That wriggled and wiggled and tickled inside her", "bird", ":How absurd", "cat", ":Fancy that", "dog", ":What a hog", "cow", "+how", "horse", "She's dead, of course"
FOR i% = 0 TO 6
  PRINT "There was an old lady who swallowed a "; swallowings$(i%, 0); "..."
  PROC_comment_on_swallowing(swallowings$(i%, 0), swallowings$(i%, 1))
  IF i% > 0 AND i% < 6 THEN
    FOR j% = i% TO 1 STEP -1
      PRINT "She swallowed the "; swallowings$(j%, 0); " to catch the "; swallowings$(j% - 1, 0); ","
    NEXT
    PROC_comment_on_swallowing(swallowings$(0, 0), swallowings$(0, 1))
  ENDIF
  PRINT
NEXT
END
:
DEF PROC_comment_on_swallowing(animal$, observation$)
CASE LEFT$(observation$, 1) OF
WHEN "+":
  PRINT "I don't know "; MID$(observation$, 2); " she swallowed a "; animal$;
  IF animal$ = "fly" THEN PRINT " -- perhaps she'll die";
  PRINT "!"
WHEN ":"
  PRINT MID$(observation$, 2); ", to swallow a "; animal$; "!"
OTHERWISE
  PRINT observation$; "!"
ENDCASE
ENDPROC

BCPL

get "libhdr"

let animal(n) = 
    n=0 -> "fly",   n=1 -> "spider",    n=2 -> "bird",
    n=3 -> "cat",   n=4 -> "dog",       n=5 -> "goat",
    n=6 -> "cow",   n=7 -> "horse",     valof finish
    
let line(n) =
    n=0 -> "I don't know why she swallowed that fly,*NPerhaps she'll die.*N",
    n=1 -> "That wiggled and jiggled and tickled inside her",
    n=2 -> "How absurd to swallow a bird",
    n=3 -> "Imagine that, she swallowed a cat!",
    n=4 -> "What a hog to swallow a dog",
    n=5 -> "She just opened her throat and swallowed that goat",
    n=6 -> "I don't know how she swallowed that cow",
    n=7 -> "She's dead, of course.",
    valof finish

let verse(n) be
$(  writef("There was an old lady who swallowed a %S,*N", animal(n))
    writef("%S*N", line(n))
    
    unless n=7 for i=n to 1 by -1
    $(  writef("She swallowed the %S to catch the %S,*N",
                    animal(i), animal(i-1))
        if i <= 2 do writef("%S*N", line(i-1))
    $)
$)

let start() be for n=0 to 7 do verse(n)

Befunge

We start with a collection of reusable phrases stored as a linked list. We then build up the sequence of indices into that list necessary to produce the song (this step is largely programmatic, because of the repetitive nature, although some of the verses require special case handling). Finally we iterate over the indices and print out the associated phrases.

055*46*146*1->00p 36268>5\:4\:2v >\#%"O"/#:3#:+#< g48*- >1-:!#v_\1+::"O"%\"O"/v
>-#2:#\8#1`#:|#-1:-1\7_^#`g00:+<>\#%"O"/#::$#<3#$+g48*-v^\,+*+ 55!:*!!-"|":g+3<
             >$ 36 26 58 49 81 36 26 10 \1-:#^\_^#:-1\+<00_@#:>#<$<
DI know an old lady who swallowed a F.|I don't know why she swallowed the 8.|Pe
rhaps she'll die.||5.|She swallowed the / to catch the $fly0. To swallow a 'spi
derS.|That wriggled and jiggled and tickled inside her%Bird/.|Quite absurd$Cat-
.|Fancy that$Dog-.|What a hog$Pig7.|Her mouth was so big%Goat=.|She just opened
 her throat$Cow3.|I don't know how'Donkey6.|It was rather wonky&Horse:.|She's d
ead, of course!|

C

#include <stdio.h>
static char const *animals[] = {
    "fly", 
    "spider", 
    "bird", 
    "cat", 
    "dog", 
    "goat", 
    "cow", 
    "horse"
};
static char const *verses[]  = {
    "I don't know why she swallowed that fly.\nPerhaps she'll die\n",
    "That wiggled and jiggled and tickled inside her",
    "How absurd, to swallow a bird",
    "Imagine that. She swallowed a cat",
    "What a hog to swallow a dog",
    "She just opened her throat and swallowed that goat",
    "I don't know how she swallowed that cow",
    "She's dead of course"
};

#define LEN(ARR) (sizeof ARR / sizeof *ARR)

int main(void)
{
    for (size_t i = 0; i < LEN(animals); i++) {
        printf("There was an old lady who swallowed a %s\n%s\n", animals[i], verses[i]);
        for (size_t j = i; j > 0 && i < LEN(animals) - 1; j--) {
            printf("She swallowed the %s to catch the %s\n", animals[j], animals[j-1]);
            if (j == 1) {
                printf("%s\n", verses[0]);
            }
        }
    }
}

C#

using System;

namespace OldLady
{
    internal class Program
    {
        private const string reason = "She swallowed the {0} to catch the {1}";
        private static readonly string[] creatures = {"fly", "spider", "bird", "cat", "dog", "goat", "cow", "horse"};

        private static readonly string[] comments =
        {
            "I don't know why she swallowed that fly.\nPerhaps she'll die\n",
            "That wiggled and jiggled and tickled inside her",
            "How absurd, to swallow a bird",
            "Imagine that. She swallowed a cat",
            "What a hog to swallow a dog",
            "She just opened her throat and swallowed that goat",
            "I don't know how she swallowed that cow",
            "She's dead of course"
        };

        private static void Main()
        {
            int max = creatures.Length;
            for (int i = 0; i < max; i++)
            {
                Console.WriteLine("There was an old lady who swallowed a {0}", creatures[i]);
                Console.WriteLine(comments[i]);
                for (int j = i; j > 0 && i < max - 1; j--)
                {
                    Console.WriteLine(reason, creatures[j], creatures[j - 1]);
                    if (j == 1)
                    {
                        Console.WriteLine(comments[j - 1]);
                    }
                }
            }
            Console.Read();
        }
    }
}

C++

Translation of: C#
#include <iostream>

const char *CREATURES[] = { "fly", "spider", "bird", "cat", "dog", "goat", "cow", "horse" };
const char *COMMENTS[] = {
    "I don't know why she swallowed that fly.\nPerhaps she'll die\n",
    "That wiggled and jiggled and tickled inside her",
    "How absurd, to swallow a bird",
    "Imagine that. She swallowed a cat",
    "What a hog to swallow a dog",
    "She just opened her throat and swallowed that goat",
    "I don't know how she swallowed that cow",
    "She's dead of course"
};

int main() {
    auto max = sizeof(CREATURES) / sizeof(char*);
    for (size_t i = 0; i < max; ++i) {
        std::cout << "There was an old lady who swallowed a " << CREATURES[i] << '\n';
        std::cout << COMMENTS[i] << '\n';
        for (int j = i; j > 0 && i < max - 1; --j) {
            std::cout << "She swallowed the " << CREATURES[j] << " to catch the " << CREATURES[j - 1] << '\n';
            if (j == 1)
                std::cout << COMMENTS[j - 1] << '\n';
        }
    }

    return 0;
}
Output:
There was an old lady who swallowed a fly
I don't know why she swallowed that fly.
Perhaps she'll die

There was an old lady who swallowed a spider
That wiggled and jiggled and tickled inside her
She swallowed the spider to catch the fly
I don't know why she swallowed that fly.
Perhaps she'll die

There was an old lady who swallowed a bird
How absurd, to swallow a bird
She swallowed the bird to catch the spider
She swallowed the spider to catch the fly
I don't know why she swallowed that fly.
Perhaps she'll die

There was an old lady who swallowed a cat
Imagine that. She swallowed a cat
She swallowed the cat to catch the bird
She swallowed the bird to catch the spider
She swallowed the spider to catch the fly
I don't know why she swallowed that fly.
Perhaps she'll die

There was an old lady who swallowed a dog
What a hog to swallow a dog
She swallowed the dog to catch the cat
She swallowed the cat to catch the bird
She swallowed the bird to catch the spider
She swallowed the spider to catch the fly
I don't know why she swallowed that fly.
Perhaps she'll die

There was an old lady who swallowed a goat
She just opened her throat and swallowed that goat
She swallowed the goat to catch the dog
She swallowed the dog to catch the cat
She swallowed the cat to catch the bird
She swallowed the bird to catch the spider
She swallowed the spider to catch the fly
I don't know why she swallowed that fly.
Perhaps she'll die

There was an old lady who swallowed a cow
I don't know how she swallowed that cow
She swallowed the cow to catch the goat
She swallowed the goat to catch the dog
She swallowed the dog to catch the cat
She swallowed the cat to catch the bird
She swallowed the bird to catch the spider
She swallowed the spider to catch the fly
I don't know why she swallowed that fly.
Perhaps she'll die

There was an old lady who swallowed a horse
She's dead of course

CLU

old_lady = cluster is swallow
    rep = null
    
    own animals: array[string] := array[string]$[
        "fly", "spider", "bird", "cat",
        "dog", "goat", "cow", "horse"
    ]
    
    own lines: array[string] := array[string]$[
        "I don't know why she swallowed that fly.\nPerhaps she'll die.\n",
        "That wiggled and jiggled and tickled inside her",
        "How absurd to swallow a bird",
        "Imagine that, she swallowed a cat!",
        "What a hog to swallow a dog",
        "She just opened her throat and swallowed that goat",
        "I don't know how she swallowed that cow",
        "She's dead, of course."
    ]
    
    verse = proc (s: stream, n: int)
        stream$putl(s, "There was an old lady who swallowed a " || animals[n])
        stream$putl(s, lines[n])
        
        if n=8 then return end
        for i: int in int$from_to_by(n, 2, -1) do
            stream$putl(s, "She swallowed the " || animals[i]
                        || " to catch the " || animals[i-1])
            if i <= 3 then stream$putl(s, lines[i-1]) end 
        end
    end verse
    
    swallow = proc (s: stream)
        for i: int in int$from_to(1, 8) do
            verse(s, i)
        end
    end swallow
end old_lady

start_up = proc ()
    old_lady$swallow(stream$primary_output())
end start_up

COBOL

        IDENTIFICATION DIVISION.
        PROGRAM-ID. OLD-LADY.

        DATA DIVISION.
        WORKING-STORAGE SECTION.

        01  LYRICS.
            03  THERE-WAS       PIC X(38) VALUE
            "There was an old lady who swallowed a ".
            03  SHE-SWALLOWED   PIC X(18) VALUE "She swallowed the ".
            03  TO-CATCH        PIC X(14) VALUE " to catch the ".
        01  ANIMALS.
            03  FLY.
                05  NAME        PIC X(6) VALUE "fly".
                05  VERSE       PIC X(60) VALUE
            "I don't know why she swallowed a fly. Perhaps she'll die.".
            03  SPIDER.
                05  NAME        PIC X(6) VALUE "spider".
                05  VERSE       PIC X(60) VALUE
            "That wiggled and jiggled and tickled inside her.".
            03  BIRD.
                05  NAME        PIC X(6) VALUE "bird".
                05  VERSE       PIC X(60) VALUE
            "How absurd, to swallow a bird.".
            03  CAT.
                05  NAME        PIC X(6) VALUE "cat".
                05  VERSE       PIC X(60) VALUE
            "Imagine that, she swallowed a cat.".
            03  DOG.
                05  NAME        PIC X(6) VALUE "dog".
                05  VERSE       PIC X(60) VALUE
            "What a hog, to swallow a dog.".
            03  GOAT.
                05  NAME        PIC X(6) VALUE "goat".
                05  VERSE       PIC X(60) VALUE
            "She just opened her throat and swallowed that goat.".
            03  COW.
                05  NAME        PIC X(6) VALUE "cow".
                05  VERSE       PIC X(60) VALUE
            "I don't know how she swallowed that cow.".
            03  HORSE.
                05  NAME        PIC X(6) VALUE "horse".
                05  VERSE       PIC X(60) VALUE
            "She's dead, of course.".
        01  ANIMAL-ARRAY REDEFINES ANIMALS.
            03  ANIMAL OCCURS 8 TIMES.
                05  NAME        PIC X(6).
                05  VERSE       PIC X(60).
        01  MISC.
            03  LINE-OUT        PIC X(80).
            03  A-IDX           PIC 9(2).
            03  S-IDX           PIC 9(2).

        PROCEDURE DIVISION.
        MAIN SECTION.
            PERFORM DO-ANIMAL
                VARYING A-IDX FROM 1 BY 1 UNTIL A-IDX > 8.
            STOP RUN.

        DO-ANIMAL SECTION.
            MOVE SPACES TO LINE-OUT.
            STRING
                THERE-WAS DELIMITED BY SIZE,
                NAME OF ANIMAL(A-IDX) DELIMITED BY SPACE,
                ","
                INTO LINE-OUT
            END-STRING.
            DISPLAY LINE-OUT.
            IF A-IDX > 1 THEN
                DISPLAY VERSE OF ANIMAL(A-IDX)
            END-IF.
            IF A-IDX = 8 THEN
                EXIT SECTION
            END-IF.
            PERFORM DO-SWALLOW 
                VARYING S-IDX FROM A-IDX BY -1 UNTIL S-IDX = 1.
            DISPLAY VERSE OF ANIMAL(1).
            DISPLAY SPACES.

        DO-SWALLOW SECTION.
            MOVE SPACES TO LINE-OUT.
            STRING
                SHE-SWALLOWED DELIMITED BY SIZE,
                NAME OF ANIMAL(S-IDX) DELIMITED BY SPACE,
                TO-CATCH DELIMITED BY SIZE,
                NAME OF ANIMAL(S-IDX - 1) DELIMITED BY SPACE
                INTO LINE-OUT
            END-STRING.
            DISPLAY LINE-OUT.

Commodore BASIC

The portion of the program that handles the lyric logic (the "No Sound" version) is universal and should work across all Commodore models. Since a sound chip is available in Commodore BASIC on the C64, Plus/4, and 128, it is not difficult to take advantage of this. The 64 and Plus/4 versions demonstrate a very rudimentary music player based on the syntax used for the Commodore 128's PLAY command (thus making the data statements nearly identical in those three versions.)

The music is not quite as procedural as the lyric strings, since the music is tailored to the unique number of syllables for each phrase, however, each verse does utilize three basic music phrases that can be iterated through.

Commodore BASIC (No Sound)

1 rem rosetta code
2 rem old lady who swallowed a fly
5 print chr$(147);chr$(14)
10 dim a$(10),ex$(10),mu$(8,3):a=1
15 for i=1 to 8:read a$(i),ex$(i):next i
20 for c=1 to 8
30   print chr$(147):print "     Old Lady Who Swallowed A Fly     ":print
40   print "I know an old lady who swallowed"
45   print "  a ";a$(c):gosub 200
50   for bc=c to 1 step -1
55     if bc=c or bc<=2 then print ex$(bc):gosub 200
57     if bc=8 then for t=1 to 1500:next
60     if bc>1 then print "She swallowed a "a$(bc)" to catch the "a$(bc-1)";"
61     gosub 200
65   next bc
70   print "   ... Perhaps she'll die!"
75   get k$:if k$="q" then end
77   if k$>"0" and k$<"9" then c=asc(k$)-49
80   print:for t=1 to 1000:next t
90 next c
100 end

200 for t=1 to 500:next t:return:rem generic delay

1000 rem lyrics
1010 data "fly","I don't know why she swallowed a fly..."
1020 data "spider","That wriggled and jiggled and tickled     inside her!"
1030 data "bird","How absurd to swallow a bird!"
1040 data "cat","Imagine that! She swallowed a cat!"
1050 data "dog","What a hog, to swallow a dog!"
1060 data "goat","She just opened her throat and swallowed  a goat!"
1070 data "cow","I don't know how she swallowed a cow!"
1080 data "horse","...She died, of course!"

Commodore 64

Sound must be played to the Commodore 64 SID chip through direct register access, therefore, the sound table is two-dimensional to account for the high byte and low byte of the appropriate frequencies.

1 rem rosetta code
2 rem old lady who swallowed a fly - c64
5 print chr$(147);chr$(14)
10 dim a$(10),ex$(10),mu$(8,3):a=1
15 for i=1 to 8:read a$(i),ex$(i):next i:gosub 2500
20 for c=1 to 8
30   print chr$(147):print "     Old Lady Who Swallowed A Fly     ":print
40   print "I know an old lady who swallowed"
45   print "  a ";a$(c):m$=mu$(c,1):gosub 2000
50   for bc=c to 1 step -1
55     if bc=c or bc<=2 then print ex$(bc):m$=mu$(bc,2):gosub 2000
57     if bc=8 then for t=1 to 2000:next
60     if bc>1 then print "She swallowed a "a$(bc)" to catch the "a$(bc-1)";"
61     if bc>1 then m$=mu$(bc,3):gosub 2000
65   next bc
70   print "   ... Perhaps she'll die!"
72   m$=mu$(1,3):gosub 2000
75   get k$:if k$="q" then end
77   if k$>"0" and k$<"9" then c=asc(k$)-49
80   print:for t=1 to 1000:next t
90 next c
100 end

1000 rem lyrics
1010 data "fly","I don't know why she swallowed a fly..."
1020 data "spider","That wriggled and jiggled and tickled     inside her!"
1030 data "bird","How absurd to swallow a bird!"
1040 data "cat","Imagine that! She swallowed a cat!"
1050 data "dog","What a hog, to swallow a dog!"
1060 data "goat","She just opened her throat and swallowed  a goat!"
1070 data "cow","I don't know how she swallowed a cow!"
1080 data "horse","...She died, of course!"

1100 rem music (optional)
1110 data "8cffaffcffa4f","8ggg4g8feec2c","8c4d8e4f":rem fly
1120 data "8cffaffcffaff","8fgggggfeccc4c","8cffaffc4f8a4f":rem spider
1130 data "8cffaffcffa4f","4g8g4g8feec2c","8cffa4f8c4f8a8ff":rem bird
1140 data "8cffaffcffa4f","8c4g8g4g8feec2c","8cffa4f8c4f8a4f":rem cat
1150 data "8cffaffcffa4f","4g8g4g8feec2c","8cffa4f8c4f8a4f":rem dog
1160 data "8cffaffcffa4f","8ccggg4g8feec2c","8cffa4f8c4f8a4f":rem goat
1170 data "8cffaffcffa4f","8ggg4g8feec2c","8cffa4f8c4f8a4f":rem cow
1180 data "8cffaffcffa2f","4c2d4e2f","8cffa4f8c4f8a4f":rem horse

2000 rem note player
2005 for z=1 to len(m$):el$=mid$(m$,z,1)
2010   if el$>="a" and a$<="g" then gosub 2050
2015   if el$>="1" and el$<="8" then du=int(ms/(asc(el$)-48))
2020 next z:return
2050 rem play note
2055 n=asc(el$)-64
2060 poke 54272,nt(n,2):poke 54273,nt(n,1):poke 54276,17
2065 for i=1 to du:next i:poke 54276,16
2070 return

2500 rem set up sound table and sid
2505 dim nt(7,2):nt(3,1)=16:nt(3,2)=195
2506 nt(4,1)=18:nt(4,2)=209
2510 nt(5,1)=21:nt(5,2)=31
2515 nt(6,1)=22:nt(6,2)=96
2520 nt(7,1)=25:nt(7,2)=30
2525 nt(1,1)=28:nt(1,2)=49
2530 nt(2,1)=31:nt(2,2)=165
2535 poke 54296,15:poke 54277,9:poke 54278,0
2540 du=250:ms=1000
2550 for i=1 to 8:for j=1 to 3:read mu$(i,j):next j:next i
2599 return

Commodore Plus/4

BASIC 3.5 on the Commodore Plus/4 at least features the SOUND command which simplifies getting the sound processor to play notes, however, a "tuned" sound table still needs to be defined with the appropriate frequencies.

1 rem rosetta code
2 rem old lady who swallowed a fly - plus/4
5 print chr$(147);chr$(14)
10 dim an$(10),ex$(10),mu$(8,3):a=1
15 for i=1 to 8:read an$(i),ex$(i):next i:gosub 2500
20 for c=1 to 8
30   print chr$(147):print "     Old Lady Who Swallowed A Fly     ":print
40   print "I know an old lady who swallowed"
45   print "  a ";an$(c):m$=mu$(c,1):gosub 2000
50   for bc=c to 1 step -1
55     if bc=c or bc<=2 then print ex$(bc):m$=mu$(bc,2):gosub 2000
57     if bc=8 then for t=1 to 2000:next t
60     if bc>1 then print "She swallowed a "an$(bc)" to catch the "an$(bc-1)";"
61     if bc>1 then m$=mu$(bc,3):gosub 2000
65   next bc
70   print "   ... Perhaps she'll die!"
72   m$=mu$(1,3):gosub 2000
75   get k$:if k$="q" then end
77   if k$>"0" and k$<"9" then c=asc(k$)-49:rem jump to animal
80   print:for t=1 to 1000:next t
90 next c
100 end

1000 rem lyrics
1010 data "fly","I don't know why she swallowed a fly..."
1020 data "spider","That wriggled and jiggled and tickled     inside her!"
1030 data "bird","How absurd to swallow a bird!"
1040 data "cat","Imagine that! She swallowed a cat!"
1050 data "dog","What a hog, to swallow a dog!"
1060 data "goat","She just opened her throat and swallowed  a goat!"
1070 data "cow","I don't know how she swallowed a cow!"
1080 data "horse","...She died, of course!"

1100 rem music (optional)
1110 data "8cffaffcffa4f","8ggg4g8feec2c","8c4d8e4f":rem fly
1120 data "8cffaffcffaff","8fgggggfeccc4c","8cffaffc4f8a4f":rem spider
1130 data "8cffaffcffa4f","4g8g4g8feec2c","8cffa4f8c4f8a8ff":rem bird
1140 data "8cffaffcffa4f","8c4g8g4g8feec2c","8cffa4f8c4f8a4f":rem cat
1150 data "8cffaffcffa4f","4g8g4g8feec2c","8cffa4f8c4f8a4f":rem dog
1160 data "8cffaffcffa4f","8ccggg4g8feec2c","8cffa4f8c4f8a4f":rem goat
1170 data "8cffaffcffa4f","8ggg4g8feec2c","8cffa4f8c4f8a4f":rem cow
1180 data "8cffaffcffa2f","4c2d4e2f","8cffa4f8c4f8a4f":rem horse

2000 rem note player
2005 for z=1 to len(m$):el$=mid$(m$,z,1)
2010 if el$>="a" and a$<="g" then gosub 2050
2015 if el$>="1" and el$<="8" then du=int(ms/(asc(el$)-48))
2020 next:return
2050 rem play note
2055 n=asc(el$)-64
2060 sound 1,nt(n),du
2065 for t=1 to du:next
2070 sound 1,0,0
2075 return

2500 rem set up sound table
2505 dim nt(7):nt(3)=596
2506 nt(4)=643
2510 nt(5)=685
2515 nt(6)=704
2520 nt(7)=739
2525 nt(1)=770
2530 nt(2)=798
2535 vol 2
2540 du=250:ms=1000
2550 for i=1 to 8:for j=1 to 3:read mu$(i,j):next j:next i
2599 return

Commodore 128

BASIC 7.0 on the Commodore 128 features a robust PLAY command which will interpret strings of macro commands for commanding the SID processor. This all but eliminates the bulk of the note playing routines. Note the data statements are slightly different as the macros for note duration are different. The 128 uses i, q, and h for eighth, quarter, and half notes respectively, while the 64 and Plus/4 examples were coded to use 8, 4, and 2 as it was simpler to use for math operations, rather than an additional look-up table.

1 rem rosetta code
2 rem old lady who swallowed a fly - c128
5 print chr$(147);chr$(14)
10 dim an$(10),ex$(10),mu$(8,3):a=1
15 for i=1 to 8:read an$(i),ex$(i):next i:gosub 2500
20 for c=1 to 8
30   print chr$(147):print "     Old Lady Who Swallowed A Fly     ":print
40   print "I know an old lady who swallowed"
45   print "  a ";an$(c):m$=mu$(c,1):gosub 2000
50   for bc=c to 1 step -1
55     if bc=c or bc<=2 then print ex$(bc):m$=mu$(bc,2):gosub 2000
57     if bc=8 then for t=1 to 2000:next t
60     if bc>1 then print "She swallowed a "an$(bc)" to catch the "an$(bc-1)";"
61     if bc>1 then m$=mu$(bc,3):gosub 2000
65   next bc
70   print "   ... Perhaps she'll die!"
72   m$=mu$(1,3):gosub 2000
75   get k$:if k$="q" then end
77   if k$>"0" and k$<"9" then c=asc(k$)-49:rem jump to animal
80   print:for t=1 to 1000:next t
90 next c
100 end

1000 rem lyrics
1010 data "fly","I don't know why she swallowed a fly..."
1020 data "spider","That wriggled and jiggled and tickled     inside her!"
1030 data "bird","How absurd to swallow a bird!"
1040 data "cat","Imagine that! She swallowed a cat!"
1050 data "dog","What a hog, to swallow a dog!"
1060 data "goat","She just opened her throat and swallowed  a goat!"
1070 data "cow","I don't know how she swallowed a cow!"
1080 data "horse","...She died, of course!"

1100 rem music (optional)
1110 data "icffaffcffaqf","igggqgifeechc","icqdieqf":rem fly
1120 data "icffaffcffaff","ifgggggfecccqc","icffaffcqfiaqf":rem spider
1130 data "icffaffcffaqf","qgigqgifeechc","icffaqficqfiaiff":rem bird
1140 data "icffaffcffaqf","icqgigqgifeechc","icffaqficqfiaqf":rem cat
1150 data "icffaffcffaqf","qgigqgifeechc","icffaqficqfiaqf":rem dog
1160 data "icffaffcffaqf","iccgggqgifeechc","icffaqficqfiaqf":rem goat
1170 data "icffaffcffaqf","igggqgifeechc","icffaqficqfiaqf":rem cow
1180 data "icffaffcffahf","qchdqehf","icffaqficqfiaqf":rem horse

2000 rem note player
2005 play m$
2010 return

2500 rem set up sid
2510 for i=1 to 8:for j=1 to 3:read mu$(i,j):next j:next i
2520 play "v1o4t0u5"
2599 return

Common Lisp

A rather iterative, rather than recursive solution. The lyrics match the original Burl Ives recording (not the later animated cartoon):

(defun verse  (what remark &optional always die) (list what remark always die))
(defun what   (verse) (first verse))
(defun remark (verse) (second verse))
(defun always (verse) (third verse))
(defun die    (verse) (fourth verse))

(defun ssa (what remark &optional always die ) 
    (verse what (format nil "~a she swallowed a ~a!" remark what always die)))
(defun tsa (what remark &optional always die) 
    (verse what (format nil "~a, to swallow a ~a!" remark what)))
(defun asa (what remark &optional always die) 
    (verse what (format nil "~a, and swallowed a ~a!" remark what)))


(let ((verses (list 
        (verse "fly" "I don't know why she swallowed the fly" T)
        (verse "spider" "That wriggled and jiggled and tickled inside her" T)
        (tsa   "bird" "Now how absurd")
        (tsa   "cat" "Now fancy that")
        (tsa   "dog" "what a hog")
        (asa   "goat" "She just opened her throat")
        (ssa   "cow" "I don't know how")
        (verse "horse" "She's dead, of course!" T T))))

  (loop for verse in verses for i from 0 doing
    (let ((it (what verse)))
      (format t "I know an old lady who swallowed a ~a~%" it)
      (format t "~a~%" (remark verse))
      (if (not (die verse)) (progn 
        (if (> i 0) 
          (loop for j from (1- i) downto 0 doing
            (let* ((v (nth j verses)))
              (format t "She swallowed the ~a to catch the ~a~%" it (what v))
              (setf it (what v))
              (if (always v)
                (format t "~a~a~%" (if (= j 0) "But " "") (remark v))))))
        (format t "Perhaps she'll die. ~%~%"))))))
Output:
I know an old lady who swallowed a fly
I don't know why she swallowed the fly
Perhaps she'll die.

I know an old lady who swallowed a spider
That wriggled and jiggled and tickled inside her
She swallowed the spider to catch the fly
But I don't know why she swallowed the fly
Perhaps she'll die.

...

I know an old lady who swallowed a cow
I don't know how she swallowed a cow!
She swallowed the cow to catch the goat
She swallowed the goat to catch the dog
She swallowed the dog to catch the cat
She swallowed the cat to catch the bird
She swallowed the bird to catch the spider
That wriggled and jiggled and tickled inside her
She swallowed the spider to catch the fly
But I don't know why she swallowed the fly
Perhaps she'll die.

I know an old lady who swallowed a horse
She's dead, of course!

Cowgol

include "cowgol.coh";

var animals: [uint8][] := {
    "fly", "spider", "bird", "cat", "dog", "goat", "cow", "horse"
};

var verses: [uint8][] := {
    "I don't know why she swallowed that fly - Perhaps she'll die.\n",
    "That wiggled and jiggled and tickled inside her!",
    "How absurd, to swallow a bird",
    "Imagine that! She swallowed a cat!",
    "What a hog to swallow a dog",
    "She just opened her throat and swallowed that goat",
    "I don't know how she swallowed that cow",
    "She's dead, of course."
};

var i: uint8 := 0;
while i < @sizeof animals loop
    print("There was an old lady who swallowed a ");
    print(animals[i]);
    print(",\n");
    print(verses[i]);
    print_nl();
    
    var j: uint8 := i;
    while j > 0 and i < @sizeof animals-1 loop
        print("She swallowed the ");
        print(animals[j]);
        print(" to catch the ");
        print(animals[j-1]);
        print(",\n");
        if j <= 2 then
            print(verses[j-1]);
            print_nl();
        end if;
        j := j - 1;
    end loop;
    
    i := i + 1;
end loop;

D

Translation of: C
import core.stdc.stdio;

immutable data = [
"_ha _c _e _p,/Quite absurd_f_p;_`cat,/Fancy that_fcat;_j`dog,/What a hog"~
"_fdog;_l`pig,/Her mouth_qso big_fpig;_d_r,/She just opened her throat_f_"~
"r;_icow,/_mhow she_ga cow;_k_o,/It_qrather wonky_f_o;_a_o_bcow,_khorse.."~
"./She's dead, of course!/","_a_p_b_e ","/S_t "," to catch the ","fly,/Bu"~
"t _mwhy s_t fly,/Perhaps she'll die!//_ha","_apig_bdog,_l`","spider,/Tha"~
"t wr_nj_ntickled inside her;_aspider_b_c",", to_s a ","_sed ","There_qan"~
" old lady who_g","_a_r_bpig,_d","_acat_b_p,_","_acow_b_r,_i","_adog_bcat"~
",_j","I don't know ","iggled and ","donkey","bird"," was ","goat"," swal"~
"low","he_gthe"];

bool oldLady(in string part, bool s=false) nothrow @nogc {
    foreach (immutable ch; part) {
        if (s)
            s = oldLady(data[ch - '_'], false);
        else if (ch == '_')
            s = true;
        else
            putchar(ch == '/' ? '\n' : ch);
    }

    return s;
}

void main() {
    data[0].oldLady;
}

A more structured alternative version:

enum Action { once, every, die }

immutable struct T {
    string anim;
    Action act;
    string phrase;
}

immutable T[10] animals = [
    T("horse",  Action.die,   "She's dead, of course!"),
    T("donkey", Action.once,  "It was rather wonky. To swallow a donkey."),
    T("cow",    Action.once,  "I don't know how. To swallow a cow."),
    T("goat",   Action.once,  "She just opened her throat. To swallow a goat."),
    T("pig",    Action.once,  "Her mouth was so big. To swallow a pig."),
    T("dog",    Action.once,  "What a hog. To swallow a dog."),
    T("cat",    Action.once,  "Fancy that. To swallow a cat."),
    T("bird",   Action.once,  "Quite absurd. To swallow a bird."),
    T("spider", Action.once,  "That wriggled and jiggled and tickled inside her."),
    T("fly",    Action.every, "I don't know why she swallowed the fly.")];

void main() {
    import std.stdio;

    foreach_reverse (immutable i; 0 .. animals.length) {
        writeln("I know an old lady who swallowed a ",
                animals[i].anim, ".");
        animals[i].phrase.writeln;

        if (animals[i].act == Action.die)
            break;

        foreach (immutable j, immutable r; animals[i + 1 .. $]) {
            writeln("She swallowed the ", animals[i + j].anim,
                    " to catch the ", r.anim, ".");
            if (r.act == Action.every)
                r.phrase.writeln;
        }

        "Perhaps she'll die.\n".writeln;
    }
}

Draco

proc nonrec animal(byte n) *char:
    case n
        incase 0: "fly"
        incase 1: "spider"
        incase 2: "bird"
        incase 3: "cat"
        incase 4: "dog"
        incase 5: "goat"
        incase 6: "cow"
        incase 7: "horse"
    esac
corp

proc nonrec line(byte n) *char:
    case n
        incase 0: "I don't know why she swallowed that fly,\r\n"
                  "Perhaps she'll die.\r\n"
        incase 1: "That wiggled and jiggled and tickled inside her,"
        incase 2: "How absurd to swallow a bird,"
        incase 3: "Imagined that, she swallowed a cat,"
        incase 4: "What a hog to swallow a dog,"
        incase 5: "She just opened her throat and swallowed that goat,"
        incase 6: "I don't know how she swallowed that cow,"
        incase 7: "She's dead, of course."
    esac
corp

proc nonrec verse(byte n) void:
    byte a;
    writeln("There was an old lady who swallowed a ", animal(n), ", ");
    writeln(line(n));
    
    if n/=7 then    
        for a from n downto 1 do
            writeln("She swallowed the ", animal(a),
                    " to catch the ", animal(a-1), ", ");
            if a <= 2 then writeln(line(a-1)) fi
        od
    fi
corp

proc nonrec main() void:
    byte n;
    for n from 0 upto 7 do verse(n) od
corp

EasyLang

Translation of: C
animals$[] = [ "fly" "spider" "bird" "cat" "dog" "goat" "cow" "horse" ]
verses$[] = [ "I don't know why she swallowed that fly.\nPerhaps she'll die\n" "That wiggled and jiggled and tickled inside her" "How absurd, to swallow a bird" "Imagine that. She swallowed a cat" "What a hog to swallow a dog" "She just opened her throat and swallowed that goat" "I don't know how she swallowed that cow" "She's dead of course" ]
for i to len animals$[]
   print "There was an old lady who swallowed a " & animals$[i]
   print verses$[i]
   if i < len animals$[]
      for j = i downto 2
         print "She swallowed the " & animals$[j] & " to catch the " & animals$[j - 1]
         if j = 2
            print verses$[1]
         .
      .
   .
.

Elena

ELENA 6.x :

import extensions;
 
const Creatures = new string[]{"fly", "spider", "bird", "cat", "dog", "goat", "cow", "horse"};
const Comments = new string[]
{
            "I don't know why she swallowed that fly"$10"Perhaps she'll die",
            "That wiggled and jiggled and tickled inside her",
            "How absurd, to swallow a bird",
            "Imagine that. She swallowed a cat",
            "What a hog to swallow a dog",
            "She just opened her throat and swallowed that goat",
            "I don't know how she swallowed that cow",
            "She's dead of course"
};
 
public program()
{
    for(int i := 0; i < Creatures.Length; i += 1)
    {
        console
            .printLineFormatted("There was an old lady who swallowed a {0}",Creatures[i])
            .printLine(Comments[i]);
 
        if(i != 0 && i != Creatures.Length - 1)
        {
            for(int j := i; j > 0; j -= 1)
            {
                console.printLineFormatted("She swallowed the {0} to catch the {1}",Creatures[j],Creatures[j - 1])
            };
 
            console.writeLine(Comments[0])
        };
 
        console.writeLine()
    }
}

Elixir

Translation of: Ruby
defmodule Old_lady do
  @descriptions [
    fly:    "I don't know why S",
    spider: "That wriggled and jiggled and tickled inside her.",
    bird:   "Quite absurd T",
    cat:    "Fancy that, S",
    dog:    "What a hog, S",
    goat:   "She opened her throat T",
    cow:    "I don't know how S",
    horse:  "She's dead, of course.",
  ]
  
  def swallowed do
    {descriptions, animals} = setup(@descriptions)
    Enum.each(Enum.with_index(animals), fn {animal, idx} ->
      IO.puts "There was an old lady who swallowed a #{animal}."
      IO.puts descriptions[animal]
      if animal == :horse, do: exit(:normal)
      if idx > 0 do
        Enum.each(idx..1, fn i ->
          IO.puts "She swallowed the #{Enum.at(animals,i)} to catch the #{Enum.at(animals,i-1)}."
          case Enum.at(animals,i-1) do
            :spider -> IO.puts descriptions[:spider]
            :fly -> IO.puts descriptions[:fly]
            _ -> :ok
          end
        end)
      end
      IO.puts "Perhaps she'll die.\n"
    end)
  end
  
  def setup(descriptions) do
    animals = Keyword.keys(descriptions)
    descs = Enum.reduce(animals, descriptions, fn animal, acc ->
              Keyword.update!(acc, animal, fn d ->
                case String.last(d) do
                  "S" -> String.replace(d, ~r/S$/, "she swallowed a #{animal}.")
                  "T" -> String.replace(d, ~r/T$/, "to swallow a #{animal}.")
                  _   -> d
                end
              end)
            end)
    {descs, animals}
  end
end

Old_lady.swallowed

Factor

Windows users should put zlib1.dll[1] to factor folder.

USING: base85 compression.zlib ;

"c%1E4%WlIU5WMphn^P`UexSD=s^-?Jk$NVE7-Gs=fQ9_`T}Y~ggi4hvMSb{SX}vpQXJ;^Yqok7%xd(0
mjR3>N1W_UQ$c@1$1#sAzsbTkHfHerT%K*K_NT><Cl4r<3ZyEa}o#KN}<)twov|KQ@`BE=GXdzugXdWO
s-E}7At$_Vm9CX{KSX)nUpq1~~%N3WyS`ZLg9$IzcccWRh+KGlek2*-;TR+lUB6EZs0X5<&U()_dvQXE
CJ#gDjv>e5yCRDAFrgX{pAnt$DPGHxt*E9$RMRBPeRcoXvT{6xN%o=~9@t{fLM`G}XV^A6Hk!HSBn{YM
ylrFhv&t_M?=}Lzm^6W<+00(I)uM#EY@ah;z@Y)zDUk;J&o^8C<;g7LlMIS{^*(al_mjFQv=BG_DyZn
<}rUt#FCDtKB9S`Y4jg+0PuB?Qt-&(11p?caq^S=1C`$D1fa<y6|YD*77a{4949T_-MVet;6abaEn"

base85> 3215 <compressed> uncompress >string print

Forth

swallow-addr is obviously a good candidate for an object, but Forth has many OO candidates - we won't settle that argument here.

: string, ( c-addr u -- ) \ store string at HERE , with a count
  dup c, here swap dup allot move ;

\ doubly linked list: (0|prev, 0|next, aside?, cstr animal; cstr aside)
\ aside? is true if the aside is always displayed.
variable swallowed
variable first
: >next ( swallow-addr -- swallow-addr' )
  cell+ @ ;
: >aside? ( swallow-addr -- f )
  2 cells + @ ;
: >animal ( swallow-addr -- c-addr u )
  3 cells + count ;
: >aside ( swallow-addr -- c-addr u )
  >animal + count ;

: swallow ( "animal" -- )
  align swallowed @ if here swallowed @ cell+ ! else here first ! then 
  here swallowed @ , swallowed !
  0 , 0 , parse-word string, ; \ data structure still needs the aside
: always ( -- )  \ set aside? of last-defined swallow to true
  swallowed @ 2 cells + on ;
: aside ( "aside" -- )
  0 parse string, ;

swallow fly always aside But I don't know why she swallowed the fly,
swallow spider always aside That wriggled and jiggled and tickled inside her;
swallow bird aside Quite absurd, she swallowed the bird;
swallow cat aside Fancy that, she swallowed the cat;
swallow dog aside What a hog, she swallowed the dog;
swallow pig aside Her mouth was so big, she swallowed the pig;
swallow goat aside She just opened her throat, she swallowed the goat;
swallow cow aside I don't know how, she swallowed the cow;
swallow donkey aside It was rather wonky, she swallowed the donkey;

: ?aside ( swallow-addr -- )  \ print aside if aside? is true
  dup >aside? if >aside cr type else drop then ;

: reasons ( swallow-addr -- )  \ print reasons she swallowed something
  begin dup @ while
    dup cr ." She swallowed the " >animal type ."  to catch the "
    @ dup >animal type ." ," dup ?aside
  repeat drop ;

: verse ( swallow-addr -- )
  cr ." There was an old lady who swallowed a " dup >animal type ." ,"
  dup >aside cr type
  reasons
  cr ." Perhaps she'll die!" ;

: song ( -- )
  first @ begin dup verse cr >next dup 0= until drop
  cr ." There was an old lady who swallowed a horse..."
  cr ." She's dead, of course!" ;

Fortran

program fly
  !A program to print the "Old lady swallowed a fly" poem
  implicit none

  character(len=52), dimension(0:8,2) :: line
  integer :: i,j
  !Define Lines of Poem
  line(1,1) = 'fly'
  line(2,1) = 'spider'
  line(3,1) = 'bird'
  line(4,1) = 'cat'
  line(5,1) = 'dog'
  line(6,1) = 'goat'
  line(7,1) = 'cow'
  line(8,1) = 'horse'
  line(0,2) = "Perhaps she'll die."
  line(1,2) = "I don't know why she swallowed that fly."
  line(2,2) = "That wiggled and jiggled and tickled inside her." 
  line(3,2) = "How absurd to swallow a bird."                      
  line(4,2) = "Imagine that. She swallowed a cat."                  
  line(5,2) = "What a hog to swallow a dog."                        
  line(6,2) = "She just opened her throat and swallowed that goat." 
  line(7,2) = "I don't know how she swallowed that cow."            
  line(8,2) = "She's dead of course."                                  

  !List each verse
  verses:do i = 1,8
     write(*,*) 'There was an old lady who swallowed a '//trim(line(i,1))//"."
     write(*,*) trim(line(i,2))
     !List things swallowed
     swallowed:do j = i,2,-1
        write(*,*) "She swallowed the "//trim(line(j,1))//" to catch the "//trim(line(j-1,1))//","
     end do swallowed
     write(*,*)  trim(line(0,2))
     write(*,*)
  end do verses
     
end program fly

FreeBASIC

dim as string lyrics(0 to 7, 0 to 1) = {_
    { "fly", "I don't know why she swallowed a fly - Perhaps she'll die!" },_
    { "spider", "That wriggled and jiggled and tickled inside her!" },_
    { "bird", "How absurd to swallow a bird!" },_
    { "cat", "Imagine that! She swallowed a cat!" },_
    { "dog", "What a hog, to swallow a dog!" },_
    { "goat", "She just opened her throat and swallowed a goat!" },_
    { "cow", "I don't know how she swallowed a cow."},_
    { "horse", "She's dead of course!" } }
    
for verse as ubyte = 0 to 7
    for countdown as byte = verse to 0 step -1
        if countdown = verse then
            print "There was an old lady who swallowed a "; lyrics(verse, 0);"."
            print lyrics(verse, 1)
            if verse = 7 then end
        end if
        if countdown > 0 then print "She swallowed the ";lyrics(countdown, 0);_
               " to catch the ";lyrics(countdown-1, 0);","
        if countdown = 2 or countdown = 1 then print lyrics(countdown-1, 1)
    next countdown
    print
next verse

Free Pascal

(* A mixture of the lyrics found in Wikipedia and the Ada version
   in Rosetta Code. It formats the lyrics like the Wikipedia one  *)
program OldLady;

uses
  SysUtils;

const
  MaxLadies = 9; //Number of iterations and array items  
  Animals: array[1..MaxLadies + 1] of shortstring = (  //Add one for the song's end
    'fly',
    'spider',
    'bird',
    'cat',
    'dog',
    'pig',
    'goat',
    'cow',
    'donkey',
    'horse'
    );

  Verse1 = 'There was an old lady who swallowed a %s;';
  //Verse 2 variations
  Verse2Var1 = '   %s'; //Doubles as a spacing formatter
  Verse2Var2 = '   %s to swallow a %s;';
  Verse2Var3 = '   %s and swallowed a %s';
  Verse2Var4 = '   %s she swallowed a %s';
  Verse3 = '   She swallowed the %s to catch the %s;';
  VerseEnd = 'I don''t know why she swallowed a fly - perhaps she''ll die!';
  SongEnd = '   ...She''s dead of course!';

  SwallowResult: array[1..MaxLadies] of shortstring = (
    VerseEnd,
    'That wiggled and jiggled and tickled inside her!',
    'Quite absurd',
    'Fancy that',
    'What a hog,',
    'Her mouth was so big',
    'She just opened her throat',
    'I don''t know how',
    'It was rather wonky'
    );

  procedure PrintSong;
  var
    i, j: byte;
    SwallowStr: shortstring;

  begin
    for i := 1 to MaxLadies do
    begin
      WriteLn(Format(Verse1, [Animals[i]]));
      case i of
        1..2: SwallowStr := Verse2Var1;
        3..5: SwallowStr := Verse2Var2;
        6, 8..9: SwallowStr := Verse2Var4;
        else
          SwallowStr := Verse2Var3;
      end;
      WriteLn(Format(SwallowStr, [SwallowResult[i], Animals[i]]));
      if i >= 2 then
      begin
        for j := i downto 2 do
        begin
          WriteLn(Format(Verse3, [Animals[j], Animals[j - 1]]));
          if (j - 1 = 2) and (i >= 3) then
            WriteLn(Format(Verse2Var1, [SwallowResult[2]]));
        end;
        if j >= 2 then
          WriteLn(Format(Verse2Var1, [VerseEnd]));
      end;
    end;
    WriteLn(Format(Verse1, [Animals[MaxLadies + 1]]));
    WriteLn(SongEnd);
  end;

begin
  PrintSong;
end.

Frege

Translation of: Haskell (old version)
Works with: Frege version 3.23.888-g4e22ab6

Nearly identical to the Haskell. Only the first line of the program is different.

module OldLady where

import Data.List

-- Once means the phrase is only printed in the verse about that animal.
-- Every means the phrase is printed for every verse.  It is used for "fly",
-- and could optionally be used for "spider", in the version of the song where
-- "wriggled and jiggled..." is repeated every verse.
-- Die is only used for the horse, and means the chain of animals won't be
-- included in the verse.
data AnimalAction = Once | Every | Die

animals = [("horse", Die, "She's dead, of course!"),
           ("donkey", Once, "It was rather wonky. To swallow a donkey."),
           ("cow", Once, "I don't know how. To swallow a cow."),
           ("goat", Once, "She just opened her throat. To swallow a goat."),
           ("pig", Once, "Her mouth was so big. To swallow a pig."),
           ("dog", Once, "What a hog. To swallow a dog."),
           ("cat", Once, "Fancy that. To swallow a cat."),
           ("bird", Once, "Quite absurd. To swallow a bird."),
           ("spider", Once, "That wriggled and jiggled and tickled inside her."),
           ("fly", Every, "I don't know why she swallowed the fly.")]

verse :: [(String, AnimalAction, String)] -> [String]
verse ((anim, act, phrase):restAnims) =
  let lns = ["I know an old lady who swallowed a " ++ anim ++ ".", phrase]
  in case act of Die -> lns
                 _ -> lns ++ verse' restAnims anim

verse' :: [(String, AnimalAction, String)] -> String -> [String]
verse' [] _ = ["Perhaps she'll die."]
verse' ((anim, act, phrase):restAnims) prevAnim =
  let why = "She swallowed the " ++ prevAnim ++ " to catch the " ++ anim ++ "."
      lns = case act of Every -> [why, phrase]
                        _ -> [why]
  in lns ++ verse' restAnims anim

song :: [String]
song = concatMap verse $ tail $ reverse $ tails animals

main = putStr $ unlines song


FutureBasic

An added feature of this code is the addition of a proper English voice reciting the rhyme back to you. This is compilable as a standalone app on M1, M2 or Intel Macs.

include "NSLog.incl"

begin enum output
  _firstAnimal = 0
  _lastAnimal  = 7
end enum

local fn OldLadySwallowedAFly
  NSUInteger i, j, numberOfAnimals
  CFMutableStringRef mutStr = fn MutableStringWithCapacity( 0 )
  
  NSLogClear
  
  CFArrayRef animals = @[@"fly", @"spider", @"bird", @"cat", @"dog", @"goat", @"cow", @"horse.."]
  CFArrayRef verses  = @[@"",¬
  @"I don't know why she swallowed the fly — perhaps she'll die!\n",¬
  @"That wriggled and jiggled and tickled inside her.",¬
  @"How absurd, to swallow a bird!",¬
  @"Imagine that, she swallowed a cat!",¬
  @"What a hog to swallow a dog!",¬
  @"She just opened her throat and swallowed that goat!",¬
  @"I wonder how she swallowed a cow?",¬
  @"She's dead, of course!"]
  
  numberOfAnimals = len(animals)
  
  for i = 0 to numberOfAnimals  -1
    NSLog( @"There was an old lady who swallowed a %@.", animals[i] ) : MutableStringAppendFormat( mutStr, @"There was an old lady who swallowed a %@.\n", animals[i] )
    if i == _firstAnimal then NSLog( @"%@", verses[1]   ) : MutableStringAppendFormat( mutStr, @"%@\n", verses[1] ) : continue
    if i >  _firstAnimal then NSLog( @"%@", verses[i+1] ) : MutableStringAppendFormat( mutStr, @"%@\n", verses[i+1] )
    if i == _lastAnimal  then break
    if ( i > 0 )
      for j = i to 1 step -1
        CFStringRef p
        if fn StringIsEqual( animals[j-1], @"fly" ) then p = @"." else p = @","
        NSLog( @"\tShe swallowed the %@ to catch the %@%@", animals[j], animals[j-1], p ) : MutableStringAppendFormat( mutStr, @"\tShe swallowed the %@ to catch the %@%@\n", animals[j], animals[j-1], p )
        if j == 2 then NSLog(@"\tThat wriggled and jiggled and tickled inside her.") : MutableStringAppendString( mutStr, @"\tThat wriggled and jiggled and tickled inside her.\n" )
        if j == 1 then NSLog( @"%@", verses[1] ) : MutableStringAppendFormat( mutStr, @"%@\n", verses[1] ) : break
      next
    end if
  next
  SpeechSynthesizerRef ref = fn SpeechSynthesizerWithVoice( @"com.apple.speech.synthesis.voice.daniel.premium" )
  fn SpeechSynthesizerStartSpeakingString( ref, mutStr )
end fn

fn OldLadySwallowedAFly

HandleEvents

The following is both printed and recited back as audio in a proper English male voice.

Output:
There was an old lady who swallowed a fly.
I don't know why she swallowed the fly — perhaps she'll die!

There was an old lady who swallowed a spider.
That wriggled and jiggled and tickled inside her.
	She swallowed the spider to catch the fly.
I don't know why she swallowed the fly — perhaps she'll die!

There was an old lady who swallowed a bird.
How absurd, to swallow a bird!
	She swallowed the bird to catch the spider,
	That wriggled and jiggled and tickled inside her.
	She swallowed the spider to catch the fly.
I don't know why she swallowed the fly — perhaps she'll die!

There was an old lady who swallowed a cat.
Imagine that, she swallowed a cat!
	She swallowed the cat to catch the bird,
	She swallowed the bird to catch the spider,
	That wriggled and jiggled and tickled inside her.
	She swallowed the spider to catch the fly.
I don't know why she swallowed the fly — perhaps she'll die!

There was an old lady who swallowed a dog.
What a hog to swallow a dog!
	She swallowed the dog to catch the cat,
	She swallowed the cat to catch the bird,
	She swallowed the bird to catch the spider,
	That wriggled and jiggled and tickled inside her.
	She swallowed the spider to catch the fly.
I don't know why she swallowed the fly — perhaps she'll die!

There was an old lady who swallowed a goat.
She just opened her throat and swallowed that goat!
	She swallowed the goat to catch the dog,
	She swallowed the dog to catch the cat,
	She swallowed the cat to catch the bird,
	She swallowed the bird to catch the spider,
	That wriggled and jiggled and tickled inside her.
	She swallowed the spider to catch the fly.
I don't know why she swallowed the fly — perhaps she'll die!

There was an old lady who swallowed a cow.
I wonder how she swallowed a cow?
	She swallowed the cow to catch the goat,
	She swallowed the goat to catch the dog,
	She swallowed the dog to catch the cat,
	She swallowed the cat to catch the bird,
	She swallowed the bird to catch the spider,
	That wriggled and jiggled and tickled inside her.
	She swallowed the spider to catch the fly.
I don't know why she swallowed the fly — perhaps she'll die!

There was an old lady who swallowed a horse...
She's dead, of course!



Go

Go Playground

package main

import "fmt"

var name, lyric, animals = 0, 1, [][]string{
	{"fly", "I don't know why she swallowed a fly. Perhaps she'll die."},
	{"spider", "That wiggled and jiggled and tickled inside her."},
	{"bird", "How absurd, to swallow a bird."},
	{"cat", "Imagine that, she swallowed a cat."},
	{"dog", "What a hog, to swallow a dog."},
	{"goat", "She just opened her throat and swallowed that goat."},
	{"cow", "I don't know how she swallowed that cow."},
	{"horse", "She's dead, of course."},
}

func main() {
	for i, animal := range animals {
		fmt.Printf("There was an old lady who swallowed a %s,\n",
			animal[name])

		if i > 0 {
			fmt.Println(animal[lyric])
		}

		// Swallowing the last animal signals her death, cutting the
		//  lyrics short.
		if i+1 == len(animals) {
			break
		}

		for ; i > 0; i-- {
			fmt.Printf("She swallowed the %s to catch the %s,\n",
				animals[i][name], animals[i-1][name])
		}

		fmt.Println(animals[0][lyric] + "\n")
	}
}

Haskell

import Data.List (tails)

animals :: [String]
animals =
  [ "fly.\nI don't know why she swallowed a fly.\nPerhaps she'll die.\n"
  , "spider.\nThat wiggled and jiggled and tickled inside her."
  , "bird.\t\nHow absurd, to swallow a bird."
  , "cat.\t\nImagine that. She swallowed a cat."
  , "dog.\t\nWhat a hog to swallow a dog."
  , "goat.\t\nShe just opened her throat and swallowed a goat."
  , "cow.\nI don't know how she swallowed a cow."
  , "horse.\nShe's dead, of course."
  ]

beginnings :: [String]
beginnings = ("There was an old lady who swallowed a " ++) <$> animals

lastVerse :: [String]
lastVerse =
  reverse
    [ "She swallowed the " ++
     takeWhile (/= '.') y ++ " to catch the " ++ takeWhile (/= '\t') x
    | (x:y:_:_) <- tails animals ]

main :: IO ()
main =
  putStr $
  concatMap unlines $
  zipWith (:) beginnings $ reverse $ ([] :) (tails lastVerse)
Output:
There was an old lady who swallowed a fly.

I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a spider. That wiggled and jiggled and tickled inside her. She swallowed the spider to catch the fly. I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a bird. How absurd, to swallow a bird. She swallowed the bird to catch the spider. That wiggled and jiggled and tickled inside her. She swallowed the spider to catch the fly. I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a cat. Imagine that. She swallowed a cat. She swallowed the cat to catch the bird. She swallowed the bird to catch the spider. That wiggled and jiggled and tickled inside her. She swallowed the spider to catch the fly. I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a dog. What a hog to swallow a dog. She swallowed the dog to catch the cat. She swallowed the cat to catch the bird. She swallowed the bird to catch the spider. That wiggled and jiggled and tickled inside her. She swallowed the spider to catch the fly. I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a goat. She just opened her throat and swallowed a goat. She swallowed the goat to catch the dog. She swallowed the dog to catch the cat. She swallowed the cat to catch the bird. She swallowed the bird to catch the spider. That wiggled and jiggled and tickled inside her. She swallowed the spider to catch the fly. I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a cow. I don't know how she swallowed a cow. She swallowed the cow to catch the goat. She swallowed the goat to catch the dog. She swallowed the dog to catch the cat. She swallowed the cat to catch the bird. She swallowed the bird to catch the spider. That wiggled and jiggled and tickled inside her. She swallowed the spider to catch the fly. I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a horse. She's dead, of course.

And a variation on this theme (a little more disaggregated):

import Prelude hiding (lookup)
import Data.Map.Strict (Map, fromList, lookup)
import Data.List (inits, intercalate)
import Data.Maybe (fromMaybe)
import Data.Bool (bool)

main :: IO ()
main = (putStrLn . unlines) (ingestion <$> meal)

meal :: [[String]]
meal = init (reverse <$> tail (inits menu)) ++ [[last menu]]

menu :: [String]
menu = fst <$> courses

courses :: [(String, String)]
courses =
  [ ("fly", "I don't know why she swallowed a fly - perhaps she'll die")
  , ("spider", "It wiggled and jiggled and tickled inside her")
  , ("bird", "How absurd, to swallow a bird")
  , ("cat", "Imagine that. She swallowed a cat")
  , ("dog", "What a hog to swallow a dog")
  , ("goat", "She just opened her throat and swallowed a goat")
  , ("cow", "I don't know how she swallowed a cow")
  , ("horse", "She died, of course")
  ]

ingestion :: [String] -> String
ingestion [] = []
ingestion dishes =
  let appetiser = head dishes
      story = motivation dishes
  in concat
       [ "\nThere was an old lady who swallowed a "
       , appetiser
       , ";\n"
       , reputation appetiser
       , "."
       , bool ("\n\n" ++ story ++ ".") [] (null story)
       ]

motivation :: [String] -> String
motivation [] = []
motivation dishes =
  intercalate ";\n" $
  zipWith
    (\a b -> concat ["She swallowed the ", a, " to catch the ", fullName b])
    dishes
    (tail dishes)

fullName :: String -> String
fullName dish
  | "spider" == dish =
    dish ++ "\nthat " ++ unwords (tail (words (reputation dish)))
  | "fly" == dish = dish ++ ".\n" ++ reputation dish
  | otherwise = dish

reputation :: String -> String
reputation = fromMaybe [] . flip lookup comments

comments :: Map String String
comments = fromList courses
Output:
There was an old lady who swallowed a fly;
I don't know why she swallowed a fly - perhaps she'll die.

There was an old lady who swallowed a spider;
It wiggled and jiggled and tickled inside her.

She swallowed the spider to catch the fly.
I don't know why she swallowed a fly - perhaps she'll die.

There was an old lady who swallowed a bird;
How absurd, to swallow a bird.

She swallowed the bird to catch the spider
that wiggled and jiggled and tickled inside her;
She swallowed the spider to catch the fly.
I don't know why she swallowed a fly - perhaps she'll die.

There was an old lady who swallowed a cat;
Imagine that. She swallowed a cat.

She swallowed the cat to catch the bird;
She swallowed the bird to catch the spider
that wiggled and jiggled and tickled inside her;
She swallowed the spider to catch the fly.
I don't know why she swallowed a fly - perhaps she'll die.

There was an old lady who swallowed a dog;
What a hog to swallow a dog.

She swallowed the dog to catch the cat;
She swallowed the cat to catch the bird;
She swallowed the bird to catch the spider
that wiggled and jiggled and tickled inside her;
She swallowed the spider to catch the fly.
I don't know why she swallowed a fly - perhaps she'll die.

There was an old lady who swallowed a goat;
She just opened her throat and swallowed a goat.

She swallowed the goat to catch the dog;
She swallowed the dog to catch the cat;
She swallowed the cat to catch the bird;
She swallowed the bird to catch the spider
that wiggled and jiggled and tickled inside her;
She swallowed the spider to catch the fly.
I don't know why she swallowed a fly - perhaps she'll die.

There was an old lady who swallowed a cow;
I don't know how she swallowed a cow.

She swallowed the cow to catch the goat;
She swallowed the goat to catch the dog;
She swallowed the dog to catch the cat;
She swallowed the cat to catch the bird;
She swallowed the bird to catch the spider
that wiggled and jiggled and tickled inside her;
She swallowed the spider to catch the fly.
I don't know why she swallowed a fly - perhaps she'll die.

There was an old lady who swallowed a horse;
She died, of course.

Icon and Unicon

This version isn't as compressed as some of the others but it is very straightforward to modify. Just add a new long and terse verse entry and amend the line marked order. This uses a feature of Icon/Unicon that allows procedures to be called with a list datatype instead of an argument list, so we just pre-build argument lists for printf.

procedure main()  #:  There Was An Old Lady Lyrics

verse := table()   # arglists for printf - [1] long asides and [2] terse joiners
verse["bird"]   := [["%s,\nQuite absurd, %s %s;\n",1,2,1],["%s,\n",1]]
verse["cat"]    := [["%s,\nFancy that, %s %s;\n",1,2,1],["%s,\n",1]]
verse["dog"]    := [["%s,\nWhat a hog, %s %s;\n",1,2,1],["%s,\n",1]]
verse["pig"]    := [["%s,\nHer mouth was so big, %s %s;\n",1,2,1],["%s,\n",1]]
verse["goat"]   := [["%s,\nShe just opened her throat, %s %s;\n",1,2,1],["%s,\n",1]]
verse["cow"]    := [["%s,\nI don't know how, %s %s;\n",1,2,1],["%s,\n",1]]
verse["donkey"] := [["%s,\nIt was rather wonky, %s %s;\n",1,2,1],["%s,\n",1]]

                   # just long versions of these 
verse["fly"]    := [["%s,\nBut I don't know why %s %s,\nPerhaps she'll die!\n\n",1,2,1]] 
verse["spider"] := [["%s,\nThat wriggled and jiggled and tickled inside her;\n",1]]
verse["horse"]  := [["%s...\nShe's dead, of course!\n",1]]

every (f := verse[k := key(verse)][1|2])[i := 1 to *f] do   # fix every printf args
   f[i] := case f[i] of { 1 : k ; 2 : "she swallowed the"; default : f[i]}
   
zoofilo := []
"fly,spider,bird,cat,dog,pig,goat,cow,donkey,horse," ?   # order
   while push(zoofilo,tab(find(","))) & move(1) do {
      printf("There was an old lady who swallowed a ")
      every critter := !zoofilo do {
         printf!verse[critter,(critter == (zoofilo[1] | "spider" | "fly"),1)|2]     
         if critter == "horse" then stop()               # dead
         printf("She swallowed the %s to catch the ","fly" ~== critter)
         }
      }
end

link printf

Sample output omitted.

printf.icn provides printf formatting

IS-BASIC

100 PROGRAM "OldLady.bas"
110 DIM A$(7),E$(7)
120 FOR N=0 TO 7
130   READ A$(N),E$(N)
140 NEXT 
150 LET M$=CHR$(13):LET L$="There was an old lady who swallowed a "
160 TEXT 80:PRINT L$;A$(1);CHR$(241)
170 FOR C=1 TO 7
180   PRINT M$;M$;L$;A$(C);
190   IF C>1 THEN
200     PRINT ";";M$;E$(C);
210     IF C<N THEN
220       FOR B=C TO 2 STEP-1
230         PRINT M$;A$(0);A$(B);" to catch the ";A$(B-1);",;"(1+ABS(B=2));
240         IF B=3 THEN PRINT M$;"  ";E$(2);
250       NEXT 
260     END IF 
270   ELSE 
280     PRINT ",";
290   END IF 
300   IF C<N THEN PRINT M$ E$(1);E$(0);
310 NEXT 
320 PRINT M$;M$;L$;"horse...";M$;"She's dead, of course!"
330 DATA "  She swallowed the "," - perhaps she'll die!"
340 DATA fly,I don't know why she swallowed a fly
350 DATA spider,"That wriggled and jiggled and tickled inside her,"
360 DATA bird,"How absurd to swallow a bird!"
370 DATA cat,"Fancy that to swallow a cat!"
380 DATA dog,"What a hog, to swallow a dog!"
390 DATA goat,"Just opened her throat and swallowwed a goat!"
400 DATA cow,"I don't know how she swallowed a cow!"

J

This defines T to be the required text.

T=:''
e=:3 :'T=:T,y,LF'
E=:e@,&'.'
O=:'I know an old lady who swallowed a 'E@,]
I=:e bind('I don''t know why she swallowed the fly.',LF,'Perhaps she''ll die.',LF)
I O 'fly'
O P=:'spider'
E 'That wriggled and jiggled and tickled inside her'
I E A=:'She swallowed the spider to catch the fly'
N=:4 :0
  O x
  E y,'. To swallow a ',x
  I E A=:'She swallowed the ',x,' to catch the ',P,'.',LF,A
  P=:x
)
'Bird'N'Quite absurd'
'Cat'N'Fancy that'
'Dog'N'What a hog'
'Pig'N'Her mouth was so big'
'Goat'N'She just opened her throat'
'Cow'N'I don''t know how'
'Donkey'N'It was rather wonky'
O'Horse'
e'She''s dead, of course!'
   T
I know an old lady who swallowed a fly.
I don't know why she swallowed the fly.
Perhaps she'll die.

I know an old lady who swallowed a spider.
That wriggled and jiggled and tickled inside her.
She swallowed the spider to catch the fly.
I don't know why she swallowed the fly.
Perhaps she'll die.

I know an old lady who swallowed a Bird.
Quite absurd. To swallow a Bird.
She swallowed the Bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed the fly.
Perhaps she'll die.

I know an old lady who swallowed a Cat.
Fancy that. To swallow a Cat.
She swallowed the Cat to catch the Bird.
She swallowed the Bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed the fly.
Perhaps she'll die.

I know an old lady who swallowed a Dog.
What a hog. To swallow a Dog.
She swallowed the Dog to catch the Cat.
She swallowed the Cat to catch the Bird.
She swallowed the Bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed the fly.
Perhaps she'll die.

I know an old lady who swallowed a Pig.
Her mouth was so big. To swallow a Pig.
She swallowed the Pig to catch the Dog.
She swallowed the Dog to catch the Cat.
She swallowed the Cat to catch the Bird.
She swallowed the Bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed the fly.
Perhaps she'll die.

I know an old lady who swallowed a Goat.
She just opened her throat. To swallow a Goat.
She swallowed the Goat to catch the Pig.
She swallowed the Pig to catch the Dog.
She swallowed the Dog to catch the Cat.
She swallowed the Cat to catch the Bird.
She swallowed the Bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed the fly.
Perhaps she'll die.

I know an old lady who swallowed a Cow.
I don't know how. To swallow a Cow.
She swallowed the Cow to catch the Goat.
She swallowed the Goat to catch the Pig.
She swallowed the Pig to catch the Dog.
She swallowed the Dog to catch the Cat.
She swallowed the Cat to catch the Bird.
She swallowed the Bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed the fly.
Perhaps she'll die.

I know an old lady who swallowed a Donkey.
It was rather wonky. To swallow a Donkey.
She swallowed the Donkey to catch the Cow.
She swallowed the Cow to catch the Goat.
She swallowed the Goat to catch the Pig.
She swallowed the Pig to catch the Dog.
She swallowed the Dog to catch the Cat.
She swallowed the Cat to catch the Bird.
She swallowed the Bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed the fly.
Perhaps she'll die.

I know an old lady who swallowed a Horse.
She's dead, of course!

Java

Translation of: C –  via D
public class OldLadySwallowedAFly {

    final static String[] data = {
        "_ha _c _e _p,/Quite absurd_f_p;_`cat,/Fancy that_fcat;_j`dog,/What a hog"
        + "_fdog;_l`pig,/Her mouth_qso big_fpig;_d_r,/She just opened her throat_f_"
        + "r;_icow,/_mhow she_ga cow;_k_o,/It_qrather wonky_f_o;_a_o_bcow,_khorse.."
        + "./She's dead, of course!/", "_a_p_b_e ", "/S_t ", " to catch the ", "fly,/Bu"
        + "t _mwhy s_t fly,/Perhaps she'll die!//_ha", "_apig_bdog,_l`", "spider,/Tha"
        + "t wr_nj_ntickled inside her;_aspider_b_c", ", to_s a ", "_sed ", "There_qan"
        + " old lady who_g", "_a_r_bpig,_d", "_acat_b_p,_", "_acow_b_r,_i", "_adog_bcat"
        + ",_j", "I don't know ", "iggled and ", "donkey", "bird", " was ", "goat", " swal"
        + "low", "he_gthe"};

    static boolean oldLady(String part, boolean s) {
        for (char c : part.toCharArray()) {
            if (s)
                s = oldLady(data[c - '_'], false);
            else if (c == '_')
                s = true;
            else
                System.out.print(c == '/' ? '\n' : c);
        }
        return s;
    }

    public static void main(String[] args) {
        oldLady(data[0], false);
    }
}

jq

Adapted from Wren

Works with: jq

Also works with gojq and fq, the Go implementations

def animals:
  ["fly", "spider", "bird", "cat", "dog", "goat", "cow", "horse"];

def phrases: [
    null,
    "That wriggled and jiggled and tickled inside her",
    "How absurd to swallow a bird",
    "Fancy that to swallow a cat",
    "What a hog, to swallow a dog",
    "She just opened her throat and swallowed a goat",
    "I don't know how she swallowed a cow",
    "\n  ...She's dead of course"
];

def sing:
  def cond(q; x): select(q) | x;
  range(0;8)
  | "There was an old lady who swallowed a \(animals[.]);",
    cond(. > 0; "\(phrases[.])"),
    cond(. < 7;
      "",
      cond(. > 0;
        range(.; 0; -1) as $j
        | "  She swallowed the \(animals[$j]) to catch the \(
               animals[$j - 1])\(if $j < 3 then ";" else "," end)",
          cond($j == 2;  "  \(phrases[1])!") ),
      "  I don't know why she swallowed a fly - Perhaps she'll die!\n" );

sing
Output:

As for Wren.

Julia

Works with: Julia version 0.6
using CodecZlib

b64 = b"""eNrtVE1rwzAMvedXaKdeRn7ENrb21rHCzmrs1m49K9gOJv9+cko/HBcGg0LHcpOfnq2np0QL
    2FuKgBbICDAoeoiKwEc0hqIUgLAxfV0tQJCdhQM7qh68kheswKeBt5ROYetTemYMCC3rii//
    WMS3WkhXVyuFAaLT261JuBWwu4iDbvYp1tYzHVS68VEIObwFgaDB0KizuFs38aSdqKv3TgcJ
    uPYdn2B1opwIpeKE53qPftxRd88Y6uoVbdPzWxznrQ3ZUi3DudQ/bcELbevqM32iCIrj3IIh
    W6plOJf6L6xaajZjzqW/qAsKIvITBGs9Nm3glboZzkVP5l6Y+0bHLnedD0CttIyrpEU5Kv7N
    Mz3XkPBc/TSN3yxGiqMiipHRekycK0ZwMhM8jerGC9zuZaoTho3kMKSfJjLaF8v8wLzmXMqM
    zJvGew/jnZPzclA08yAkikegDTTUMfzwDXBcwoE="""
println(String(transcode(ZlibDecompressor(), base64decode(b64))))
animals = [
    ("fly", "I don't know why she swallowed a fly, perhaps she'll die."),
    ("spider", "It wiggled and jiggled and tickled inside her."),
    ("bird", "How absurd, to swallow a bird."),
    ("cat", "Imagine that, she swallowed a cat."),
    ("dog", "What a hog, to swallow a dog."),
    ("goat", "She just opened her throat and swallowed a goat."),
    ("cow", "I don't know how she swallowed a cow."),
    ("horse", "She's dead, of course.")]

for (i, (animal, lyric)) in enumerate(animals)
    println("There was an old lady who swallowed a $animal.\n$lyric")

    if animal == "horse" break end

    for ((predator, _), (prey, _)) in zip(animals[i:-1:1], animals[i-1:-1:1])
        println("\tShe swallowed the $predator to catch the $prey")
    end

    if animal != "fly" println(animals[1][2]) end  # fly lyric
    println()  # new line
end

Kotlin

// version 1.1.3

val animals = listOf("fly", "spider", "bird", "cat","dog", "goat", "cow", "horse")

val phrases = listOf(
    "",
    "That wriggled and jiggled and tickled inside her",
    "How absurd to swallow a bird",
    "Fancy that to swallow a cat",
    "What a hog, to swallow a dog",
    "She just opened her throat and swallowed a goat",
    "I don't know how she swallowed a cow",
    "\n  ...She's dead of course"
)

fun sing() {
    for (i in 0..7) {
       println("There was an old lady who swallowed a ${animals[i]};")
       if (i > 0) println("${phrases[i]}!")
       if (i == 7) return
       println()                  
       if (i > 0) {
           for (j in i downTo 1) {
               print("  She swallowed the ${animals[j]} to catch the ${animals[j - 1]}")
               println(if (j < 3) ";" else ",")
               if (j == 2) println("  ${phrases[1]}!")               
           }
       }
       println("  I don't know why she swallowed a fly - Perhaps she'll die!\n")
    }
}  

fun main(args: Array<String>) {
    sing()
}

Lambdatalk

{def A {A.new fly spider bird cat dog goat cow horse}}
-> A

{def H
 {H.new
   fly    I don't know why she swallowed that fly{br}Perhaps she'll die | 
   spider That wiggled and jiggled and tickled inside her |
   bird   How absurd, to swallow a bird |
   cat    Imagine that. She swallowed a cat |
   dog    What a hog to swallow a dog |
   goat   She just opened her throat and swallowed that goat |
   cow    I don't know how she swallowed that cow |
   horse  She's dead of course
}}
-> H

{def oldlady {lambda {:w} There was an old lady who swallowed a :w}}
-> oldlady

{def swallow {lambda {:a :b} She swallowed the :a to catch the :b}}
-> swallow

Writing

{hr}{oldlady {A.get 0 {A}}}
{H.get {A.get 0 {A}} {H}}

{S.map {lambda {:i}
               {hr}{oldlady {A.get :i {A}}}
               {br}{H.get {A.get :i {A}} {H}}
               {S.map {lambda {:j} {br}* {swallow {A.get :j {A}}
                                                  {A.get {- :j 1} {A}}}}
                      {S.serie :i 1 -1}} 
               {br}{H.get {A.get 0 {A}} {H}} } 
       {S.serie 1 6}}

{hr}{oldlady {A.get 7 {A}}}
{H.get {A.get 7 {A}} {H}} 

displays:

There was an old lady who swallowed a fly
I don't know why she swallowed that fly
Perhaps she'll die

There was an old lady who swallowed a spider 
That wiggled and jiggled and tickled inside her 
* She swallowed the spider to catch the fly 
I don't know why she swallowed that fly
Perhaps she'll die 

There was an old lady who swallowed a bird 
How absurd, to swallow a bird 
* She swallowed the bird to catch the spider 
* She swallowed the spider to catch the fly 
I don't know why she swallowed that fly
Perhaps she'll die 

...

There was an old lady who swallowed a cow 
I don't know how she swallowed that cow 
* She swallowed the cow to catch the goat 
* She swallowed the goat to catch the dog 
* She swallowed the dog to catch the cat 
* She swallowed the cat to catch the bird 
* She swallowed the bird to catch the spider 
* She swallowed the spider to catch the fly 
I don't know why she swallowed that fly
Perhaps she'll die

There was an old lady who swallowed a horse
She's dead of course

Liberty BASIC

'[RC] Old lady swallowed a fly
'http://rosettacode.org/wiki/Old_lady_swallowed_a_fly
'lyrics
'http://www.timmyabell.com/music/lyrics/ol/oldlady.htm

animalList$="fly spider bird cat dog goat cow horse"
reason$(1)="I don't know why she swallowed the fly,"
reason$(2)="That wriggled and jiggled and tickled inside her."
reason$(3)="How absurd to swallow a bird!"
reason$(4)="Imagine that, to swallow a cat!"
reason$(5)="My, what a hog, to swallow a dog!"
reason$(6)="Just opened her throat and swallowed a goat!"
reason$(7)="I wonder how she swallowed a cow?!"
reason$(8)="She's dead, of course!!"

i=0
while 1
    i=i+1
    animal$ = word$(animalList$, i)
    if animal$ ="" then exit while
    verse$ = "I know an old lady who "
    verse2$ = "swallowed a " +animal$ 
    print verse$ +verse2$+","
    print reason$(i)
    if i = 8 then end
    '--------------
    animals$=animal$+" "+animals$
    animal2$="*"
    j=1
    while 1
        j=j+1
        animal2$ = word$(animals$, j)
        if animal2$ ="" then exit while
        reason$="She swallowed the "+animal$+" to catch the "+animal2$+","
        animal$ = animal2$
        print reason$
        if animal2$ = "fly" then print reason$(1)
        if animal2$ = "spider" then print reason$(2)
    wend
    '--------------
    print "I guess she'll die."
    print
wend

end

make "data [
; animal inc comment
  [fly    2 [I don't know why she swallowed that fly]]
  [spider 2 [That wriggled and jiggled and tickled inside her]]
  [bird   1 [Quite absurd, to swallow a bird]]
  [cat    1 [How about that, to swallow a cat]]
  [dog    1 [What a hog, to swallow a dog]]
  [pig    1 [Her mouth was so big to swallow a pig]]
  [goat   1 [She just opened her throat to swallow a goat.]]
  [cow    1 [I don't know how she swallowed a cow.]]
  [donkey 1 [It was rather wonky to swallow a donkey]]
  [horse  0 [She's dead, of course!]]
]

foreach :data [
  local "i make "i #
  (local "animal "include "comment)
  (foreach [animal include comment] ? "make)
  print se [There was an old lady who swallowed a] :animal
  print :comment
  if greater? :include 0 [
    if greater? :i 1 [
      repeat difference :i 1 [
        local "j make "j difference :i repcount 
        print (se [She swallowed the] (first item sum 1 :j :data) 
                  [to catch the] (first item :j :data))
        if greater? item 2 item :j :data 1 [print item 3 item :j :data]
      ]
    ]
    print [Perhaps she'll die]
    print "
  ]
]

bye

Lua

animals = {"fly", "spider", "bird", "cat","dog", "goat", "cow", "horse"}
phrases = {
    "",
    "That wriggled and jiggled and tickled inside her",
    "How absurd to swallow a bird",
    "Fancy that to swallow a cat",
    "What a hog, to swallow a dog",
    "She just opened her throat and swallowed a goat",
    "I don't know how she swallowed a cow",
    "  ...She's dead of course"
}

for i=0,7 do
    io.write(string.format("There was an old lady who swallowed a %s\n", animals[i+1]))
    if i>0 then io.write(phrases[i+1]) end
    if i==7 then break end
    if i>0 then
        io.write("\n")
        for j=i,1,-1 do
            io.write(string.format("She swallowed the %s to catch the %s", animals[j+1], animals[j]))
            -- if j<4 then p='.' else p=',' end
            -- io.write(string.format("%s\n", p))
            io.write("\n")
            if j==2 then
                io.write(string.format("%s!\n", phrases[2]))
            end
        end
    end
    io.write("I don't know why she swallowed a fly - Perhaps she'll die!\n\n")
end

MAD

            NORMAL MODE IS INTEGER
            
            INTERNAL FUNCTION(V)
            ENTRY TO VERSE.
            TRANSFER TO VS(V+1)
VS(1)       PRINT COMMENT$ I DON'T KNOW WHY SHE SWALLOWED THAT FLY$
            PRINT COMMENT$ PERHAPS SHE'LL DIE$
            PRINT COMMENT$ $
            FUNCTION RETURN V
VS(2)       PRINT COMMENT
          0      $ THAT WIGGLED AND JIGGLED AND TICKLED INSIDE HER$
            FUNCTION RETURN V
VS(3)       PRINT COMMENT$ HOW ABSURD TO SWALLOW A BIRD!$
            FUNCTION RETURN V
VS(4)       PRINT COMMENT$ IMAGINE THAT - SHE SWALLOWED A CAT!$
            FUNCTION RETURN V
VS(5)       PRINT COMMENT$ WHAT A HOG TO SWALLOW A DOG$
            FUNCTION RETURN V
VS(6)       PRINT COMMENT
          0   $ SHE JUST OPENED HER THROAT AND SWALLOWED THAT GOAT$
            FUNCTION RETURN V
VS(7)       PRINT COMMENT$ I DON'T KNOW HOW SHE SWALLOWED THAT COW$
            FUNCTION RETURN V
VS(8)       PRINT COMMENT$ SHE'S DEAD, OF COURSE.$
            END OF FUNCTION
            
            VECTOR VALUES ANIMAL = 
          0  $FLY$,$SPIDER$,$BIRD$,$CAT$,$DOG$,$GOAT$,$COW$,$HORSE$
            
            VECTOR VALUES LADY =
          0      $38HTHERE WAS AN OLD LADY WHO SWALLOWED A ,C,1H,*$
           
            VECTOR VALUES SWALLO =
          0    $18HSHE SWALLOWED THE ,C,S1,13HTO CATCH THE ,C,1H,*$
          
            THROUGH VERSE, FOR I=0, 1, I.G.7
            PRINT FORMAT LADY, ANIMAL(I)
            VERSE.(I)
            THROUGH VERSE, FOR J=I, -1, J.E.0 .OR. I.GE.7
            PRINT FORMAT SWALLO, ANIMAL(J), ANIMAL(J-1)
VERSE       WHENEVER J.LE.2, VERSE.(J-1)
                       
            END OF PROGRAM

Maple

swallowed := ["fly", "spider", "bird", "cat", "dog", "cow", "horse"]:
phrases := ["I don't know why she swallowed a fly, perhaps she'll die!",
		  "That wriggled and wiggled and tiggled inside her.",
		  "How absurd to swallow a bird.",
		  "Fancy that to swallow a cat!",
		  "What a hog, to swallow a dog.",
		  "I don't know how she swallowed a cow.",
		  "She's dead, of course."]:
for i to numelems(swallowed) do
	printf("There was an old lady who swallowed a %s.\n%s\n", swallowed[i], phrases[i]);
	if i > 1 and i < 7 then
		for j from i by -1 to 2 do
			printf("\tShe swallowed the %s to catch the %s.\n", swallowed[j], swallowed[j-1]);
		end do;
		printf("%s\n\n", phrases[1]);
	elif i = 1 then
		printf("\n");
	end if;
end do;
Output:
There was an old lady who swallowed a fly.
I don't know why she swallowed a fly, perhaps she'll die!

There was an old lady who swallowed a spider.
That wriggled and wiggled and tiggled inside her.
	She swallowed the spider to catch the fly.
I don't know why she swallowed a fly, perhaps she'll die!

There was an old lady who swallowed a bird.
How absurd to swallow a bird.
	She swallowed the bird to catch the spider.
	She swallowed the spider to catch the fly.
I don't know why she swallowed a fly, perhaps she'll die!

There was an old lady who swallowed a cat.
Fancy that to swallow a cat!
	She swallowed the cat to catch the bird.
	She swallowed the bird to catch the spider.
	She swallowed the spider to catch the fly.
I don't know why she swallowed a fly, perhaps she'll die!

There was an old lady who swallowed a dog.
What a hog, to swallow a dog.
	She swallowed the dog to catch the cat.
	She swallowed the cat to catch the bird.
	She swallowed the bird to catch the spider.
	She swallowed the spider to catch the fly.
I don't know why she swallowed a fly, perhaps she'll die!

There was an old lady who swallowed a cow.
I don't know how she swallowed a cow.
	She swallowed the cow to catch the dog.
	She swallowed the dog to catch the cat.
	She swallowed the cat to catch the bird.
	She swallowed the bird to catch the spider.
	She swallowed the spider to catch the fly.
I don't know why she swallowed a fly, perhaps she'll die!

There was an old lady who swallowed a horse.
She's dead, of course.

Mathematica /Wolfram Language

animals = {"fly", "spider", "bird", "cat", "dog", "goat", "cow", 
   "horse"};
notes = {"", "That wiggled and jiggled and tickled inside her.\n", 
   "How absurd, to swallow a bird.\n", 
   "Imagine that. She swallowed a cat.\n", 
   "What a hog to swallow a dog.\n", 
   "She just opened her throat and swallowed that goat.\n", 
   "I don't know how she swallowed that cow.\n", 
   "She's dead, of course.", 
   "I don't know why she swallowed that fly.\nPerhaps she'll die.\n\n\
"};
Print[StringJoin @@ ("There was an old lady who swallowed a " <> 
       animals[[#]] <> ".\n" <> notes[[#]] <> 
       If[# == 8, "", 
        StringJoin @@ ("She swallowed the " <> animals[[#]] <> 
              " to catch the " <> animals[[# - 1]] <> ".\n" & /@ 
            Range[#, 2, -1]) <> notes[[9]]] & /@ Range[8])];
Output:
There was an old lady who swallowed a fly.
I don't know why she swallowed that fly.
Perhaps she'll die.

There was an old lady who swallowed a spider.
That wiggled and jiggled and tickled inside her.
She swallowed the spider to catch the fly.
I don't know why she swallowed that fly.
Perhaps she'll die.

There was an old lady who swallowed a bird.
How absurd, to swallow a bird.
She swallowed the bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed that fly.
Perhaps she'll die.

There was an old lady who swallowed a cat.
Imagine that. She swallowed a cat.
She swallowed the cat to catch the bird.
She swallowed the bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed that fly.
Perhaps she'll die.

There was an old lady who swallowed a dog.
What a hog to swallow a dog.
She swallowed the dog to catch the cat.
She swallowed the cat to catch the bird.
She swallowed the bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed that fly.
Perhaps she'll die.

There was an old lady who swallowed a goat.
She just opened her throat and swallowed that goat.
She swallowed the goat to catch the dog.
She swallowed the dog to catch the cat.
She swallowed the cat to catch the bird.
She swallowed the bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed that fly.
Perhaps she'll die.

There was an old lady who swallowed a cow.
I don't know how she swallowed that cow.
She swallowed the cow to catch the goat.
She swallowed the goat to catch the dog.
She swallowed the dog to catch the cat.
She swallowed the cat to catch the bird.
She swallowed the bird to catch the spider.
She swallowed the spider to catch the fly.
I don't know why she swallowed that fly.
Perhaps she'll die.

There was an old lady who swallowed a horse.
She's dead, of course.

Mercury

:- module oldlady.
:- interface.
:- import_module io.
:- pred main(io::di, io::uo) is det.
:- implementation.
:- import_module list, string.

:- type animal
    --->    horse
    ;       donkey
    ;       cow
    ;       goat
    ;       pig
    ;       dog
    ;       cat
    ;       bird
    ;       spider
    ;       fly.

:- func verse(animal) = string.
verse(horse)    = "She's dead, of course!".
verse(donkey)   = "It was rather wonky. To swallow a donkey.".
verse(cow)      = "I don't know how. To swallow a cow.".
verse(goat)     = "She just opened her throat. To swallow a goat.".
verse(pig)      = "Her mouth was so big. To swallow a pig.".
verse(dog)      = "What a hog. To swallow a dog.".
verse(cat)      = "Fancy that. To swallow a cat.".
verse(bird)     = "Quite absurd. To swallow a bird.".
verse(spider)   = "That wriggled and jiggled and tickled inside her.".
verse(fly)      = "I don't know why she swallowed the fly.".

:- pred tocatch(animal, animal).
:- mode tocatch(in, out) is semidet.
:- mode tocatch(out, in) is semidet.
tocatch(horse, donkey).
tocatch(donkey, cow).
tocatch(cow, goat).
tocatch(goat, pig).
tocatch(pig, dog).
tocatch(dog, cat).
tocatch(cat, bird).
tocatch(bird, spider).
tocatch(spider, fly).

:- pred swallow(animal::in, io::di, io::uo) is det.
swallow(A, !IO) :-
    ( if tocatch(A, B) then
        io.format("She swallowed the %s to catch the %s.\n",
            [s(string(A)), s(string(B))], !IO),
        swallow(B, !IO)
    else
        io.format("%s\nPerhaps she'll die.\n\n", [s(verse(fly))], !IO)
    ).

:- pred swallowed(animal::in, io::di, io::uo) is det.
swallowed(A, !IO) :-
    io.format("I know an old lady who swallowed a %s.\n", [s(string(A))], !IO),
    ( if A = horse then
        io.write_string("She's dead, of course!\n", !IO)
    else if A = fly, tocatch(B, A) then
        swallow(A, !IO),
        swallowed(B, !IO)
    else if tocatch(B, A) then
        io.write_string(verse(A), !IO),
        io.nl(!IO),
        swallow(A, !IO),
        swallowed(B, !IO)
    else
        true
    ).

main(!IO) :-
    swallowed(fly, !IO).

Modula-2

MODULE OldLady;
FROM FormatString IMPORT FormatString;
FROM Terminal IMPORT WriteString,WriteLn,ReadChar;

TYPE
    AA = ARRAY[0..7] OF ARRAY[0..7] OF CHAR;
    VA = ARRAY[0..7] OF ARRAY[0..63] OF CHAR;
VAR
    buf : ARRAY[0..127] OF CHAR;
    animals : AA;
    verses : VA;
    i,j : INTEGER;
BEGIN
    FormatString("I don't know why she swallowed that fly.\nPerhaps she'll die\n", buf);

    animals := AA{"fly", "spider", "bird", "cat", "dog", "goat", "cow", "horse"};
    verses := VA{
        "I don't know why she swallowed that fly.",
        "That wiggled and jiggled and tickled inside her",
        "How absurd, to swallow a bird",
        "Imagine that. She swallowed a cat",
        "What a hog to swallow a dog",
        "She just opened her throat and swallowed that goat",
        "I don't know how she swallowed that cow",
        "She's dead of course"
    };

    FOR i:=0 TO 7 DO
        FormatString("There was an old lady who swallowed a %s\n%s\n", buf, animals[i], verses[i]);
        WriteString(buf);
        IF i=0 THEN
            WriteString("Perhaps she'll die");
            WriteLn;
            WriteLn;
        END;
        j := i;
        WHILE (j>0) AND (i<7) DO
            FormatString("She swallowed the %s to catch the %s\n", buf, animals[j], animals[j-1]);
            WriteString(buf);
            IF j=1 THEN
                WriteString(verses[0]);
                WriteLn;
                WriteString("Perhaps she'll die");
                WriteLn;
                WriteLn
            END;
            DEC(j)
        END;
    END;

    ReadChar
END OldLady.

Nanoquery

Translation of: Ursa
reason          = {"She swallowed the ", " to catch the "}
creatures       = {"fly", "spider", "bird", "cat", "dog", "goat", "cow", "horse"}
comments        = {"I don't know why she swallowed that fly.\nPerhaps she'll die\n",\
                   "That wiggled and jiggled and tickled inside her",\
                   "How absurd, to swallow a bird",\
                   "Imagine that. She swallowed a cat",\
                   "What a hog to swallow a dog",\
                   "She just opened her throat and swallowed that goat",\
                   "I don't know how she swallowed that cow",\
                   "She's dead of course"}

max = len(creatures)
for i in range(0, max - 1)
    println "There was an old lady who swallowed a " + creatures[i]
    println comments[i]
    for (j = i) ((j > 0) && (i < (max - 1))) (j -= 1)
        println reason[0] + creatures[j] + reason[1] + creatures[j - 1]
        if j = 1
            println comments[j - 1]
        end
    end
end

input()

Nim

Translation of: Python
Library: nim-lang/zip
import zip/zlib, base64

const b64 = """
eNrtVE1rwzAMvedXaKdeRn7ENrb21rHCzmrs1m49K9gOJv9+cko/HBcGg0LHcpOfnq2np0QL
2FuKgBbICDAoeoiKwEc0hqIUgLAxfV0tQJCdhQM7qh68kheswKeBt5ROYetTemYMCC3rii//
WMS3WkhXVyuFAaLT261JuBWwu4iDbvYp1tYzHVS68VEIObwFgaDB0KizuFs38aSdqKv3TgcJ
uPYdn2B1opwIpeKE53qPftxRd88Y6uoVbdPzWxznrQ3ZUi3DudQ/bcELbevqM32iCIrj3IIh
W6plOJf6L6xaajZjzqW/qAsKIvITBGs9Nm3glboZzkVP5l6Y+0bHLnedD0CttIyrpEU5Kv7N
Mz3XkPBc/TSN3yxGiqMiipHRekycK0ZwMhM8jerGC9zuZaoTho3kMKSfJjLaF8v8wLzmXMqM
zJvGew/jnZPzclA08yAkikegDTTUMfzwDXBcwoE="""

echo b64.decode.uncompress()

OCaml

Using a dictionary

Only one minimalist line of code (the last line):

let d = [|
  "I know an old lady who swallowed a "; "fly"; ".\n";
  "I don't know why she swallowed the fly.\nPerhaps she'll die.\n\n";
  "spider"; "That wriggled and jiggled and tickled inside her";
  "She swallowed the "; " to catch the "; "Bird"; "Quite absurd";
  ". To swallow a "; "Cat"; "Fancy that"; "Dog"; "What a hog"; "Pig";
  "Her mouth was so big"; "Goat"; "She just opened her throat"; "Cow";
  "I don't know how"; "Donkey"; "It was rather wonky";
  "I know an old lady who swallowed a Horse.\nShe's dead, of course!\n";
|]

let s0 = [6;4;7;1;2;3]
let s1 = [6;8;7;4;2]   @ s0
let s2 = [6;11;7;8;2]  @ s1
let s3 = [6;13;7;11;2] @ s2
let s4 = [6;15;7;13;2] @ s3
let s5 = [6;17;7;15;2] @ s4
let s6 = [6;19;7;17;2] @ s5
let s7 = [6;21;7;19;2] @ s6

let s =
  [0;1;2;3;0;4;2;5;2] @ s0 @
  [0;8;2;9;10;8;2]    @ s1 @
  [0;11;2;12;10;11;2] @ s2 @
  [0;13;2;14;10;13;2] @ s3 @
  [0;15;2;16;10;15;2] @ s4 @
  [0;17;2;18;10;17;2] @ s5 @
  [0;19;2;20;10;19;2] @ s6 @
  [0;21;2;22;10;21;2] @ s7 @
  [23] ;;

List.iter (fun i -> print_string d.(i)) s

Using dictionary based decompression

Translation of: D

Here we use the function String.fold_left 1 which is not available in the standard library but in the extlib:

let dict = [|
  "_ha _c _e _p,\nQuite absurd_f_p;_`cat,\nFancy that_fcat;_j`dog,\nWhat a hog_\
  fdog;_l`pig,\nHer mouth_qso big_fpig;_d_r,\nShe just opened her throat_f_r;_i\
  cow,\n_mhow she_ga cow;_k_o,\nIt_qrather wonky_f_o;_a_o_bcow,_khorse...\nShe'\
  s dead, of course!\n";"_a_p_b_e ";"\nS_t ";" to catch the ";"fly,\nBut _mwhy \
  s_t fly,\nPerhaps she'll die!\n\n_ha";"_apig_bdog,_l`";"spider,\nThat wr_nj_n\
  tickled inside her;_aspider_b_c";", to_s a ";"_sed ";"There_qan old lady who_\
  g";"_a_r_bpig,_d";"_acat_b_p,_";"_acow_b_r,_i";"_adog_bcat,_j";"I don't know \
  ";"iggled and ";"donkey";"bird";" was ";"goat";" swallow";"he_gthe" |]
 
let rec old_lady part s =
  ExtString.String.fold_left (fun s c ->
    if s then old_lady dict.(Char.code c - 95) false
    else if c = '_' then true
    else (print_char c; s)
  ) s part
 
let _ =
  old_lady dict.(0) false

Using Logic

let an =
  [| "fly"; "spider"; "bird"; "cat"; "dog"; "pig"; "goat"; "cow"; "donkey" |]

let cm =
  [| "Quite absurd";
     "Fancy that";
     "What a hog";
     "Her mouth was so big";
     "She just opened her throat";
     "I don't know how";
     "It was rather wonky"; |]

let p = Printf.printf

let h n =
  for i = n downto 1 do
    if i = 1 then
      p "That wriggled and jiggled and tickled inside her;\n";
    p "She swallowed the %s to catch the %s,\n" an.(i) an.(i-1)
  done

let g n =
  if n >= 2 then p "%s, to swallow a %s;\n" cm.(n-2) an.(n)

let f n =
  p "There was an old lady who swallowed a %s,\n" an.(n); g n; h n;
  p "But I don't know why she swallowed the fly,\nPerhaps she'll die!\n\n"

let () =
  for i = 0 to 8 do f i done;
  p "There was an old lady who swallowed a horse...\n\
     She's dead, of course!"

Perl

Using string subst:

my @animals = (
	"fly",
	"spider/That wriggled and jiggled and tickled inside her.\n",
	"bird//Quite absurd!",
	"cat//Fancy that!",
	"dog//What a hog!",
	"pig//Her mouth was so big!",
	"goat//She just opened her throat!",
	"cow//I don't know how;",
	"donkey//It was rather wonkey!",
	"horse:",
);

my $s = "swallow";
my $e = $s."ed";
my $t = "There was an old lady who $e a ";
my $_ = $t."But I don't know why she $e the fly;\nPerhaps she'll die!\n\n";

my ($a, $b, $c, $d);
while (my $x = shift @animals) {
	s/$c//;
	($a, $b, $c) = split('/', $x);
	$d = " the $a";

	$c =~ s/;/ she $e$d;\n/;
	$c =~ s/!/, to $s$d;\n/;

	s/$t/"$t$a,\n$c".(($b||$c) && "${b}She $e$d to catch the ")/e;

	s/:.*/--\nShe's dead, of course!\n/s;
	print;
}

Using compression: (Assumes a Unix-like OS and the availability of the uudecode and bunzip2 utilities).

open OUT, "| uudecode | bunzip2" and
print OUT <DATA> and
close OUT;

__DATA__
begin-base64 644 -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====

Phix

Translation of: Ada
with javascript_semantics 
sequence lines = {"Perhaps she'll die!\n"}, animals = {}
 
procedure swallow(string animal, second_line, integer permanent_second_line=TRUE)
    printf(1,"There was an old lady who swallowed a %s,\n%s\n",{animal,second_line})
    if length(animals)!=0 then
        lines = prepend(lines,sprintf("She swallowed the %s to catch the %s,\n",{animal,animals[$]}))
    end if
    printf(1,"%s\n",{join(lines,"")})
    if permanent_second_line then
        lines = prepend(lines,second_line&"\n")
    end if
    animals = append(animals,animal)
end procedure
 
procedure swallow_all(sequence all)
    for i=1 to length(all) do
        string {animal,line2} = all[i]
        swallow(animal, sprintf("%s, %s a %s;",{line2,iff(animal="cow"?"she swallowed":"to swallow"),animal}), FALSE);
    end for
end procedure
 
swallow("fly", "But I don't know why she swallowed the fly,");
swallow("spider",  "That wriggled and jiggled and tickled inside her;");
swallow_all({{"bird", "Quite absurd"},{"cat", "Fancy that"},{"dog", "What a hog"},
             {"pig", "Her mouth was so big"},{"goat","She just opened her throat"},
             {"cow", "I don't know how"},{"donkey", "It was rather wonky"}})
printf(1, "There was an old lady who swallowed a horse ...\nShe's dead, of course!")

PHP

<?php

$swallowed = array(
  array('swallowed' => 'fly.',
        'reason' => "I don't know why she swallowed the fly."),
  array('swallowed' => 'spider,',
        'aside' => "which wiggled and jiggled and tickled inside her.",
        'reason' => "She swallowed the spider to catch the fly"),
  array('swallowed' => 'bird.',
        'aside' => "How absurd! To swallow a bird!",
        'reason' => "She swallowed the bird to catch the spider,"),
  array('swallowed' => 'cat.',
        'aside' => "Imagine that! To swallow a cat!",
        'reason' => "She swallowed the cat to catch the bird."),
  array('swallowed' => 'dog.',
        'aside' => "What a hog! To swallow a dog!",
        'reason' => "She swallowed the dog to catch the cat."),
  array('swallowed' => 'horse',
        'aside' => "She's dead, of course. She swallowed a horse!",
        'reason' => "She swallowed the horse to catch the dog."));

foreach($swallowed as $creature)
{
  print "I knew an old lady who swallowed a " . $creature['swallowed'] . "\n";
  if(array_key_exists('aside', $creature))
    print $creature['aside'] . "\n";

  $reversed = array_reverse($swallowed);
  $history = array_slice($reversed, array_search($creature, $reversed));

  foreach($history as $note)
  {
    print $note['reason'] . "\n";
  }

  if($swallowed[count($swallowed) - 1] == $creature)
    print "But she sure died!\n";
  else
    print "Perhaps she'll die." . "\n\n";
}

PicoLisp

Translation of: C
(de *Dict
   `(chop
      "_ha _c _e _p,/Quite absurd_f_p;_`cat,/Fancy that_fcat;_j`dog,\
         /What a hog_fdog;_l`pig,/Her mouth_qso big_fpig;_d_r,/She just \
         opened her throat_f_r;_icow,/_mhow she_ga cow;_k_o,/It_qrather \
         wonky_f_o;_a_o_bcow,_khorse.../She's dead, of course!/" )
   `(chop "_a_p_b_e ")
   `(chop "/S_t ")
   `(chop " to catch the ")
   `(chop "fly,/But _mwhy s_t fly,/Perhaps she'll die!//_ha")
   `(chop "_apig_bdog,_l`")
   `(chop "spider,/That wr_nj_ntickled inside her;_aspider_b_c")
   `(chop ", to_s a ")
   `(chop "_sed ")
   `(chop "There_qan old lady who_g")
   `(chop "_a_r_bpig,_d")
   `(chop "_acat_b_p,_")
   `(chop "_acow_b_r,_i")
   `(chop "_adog_bcat,_j")
   `(chop "I don't know ")
   `(chop "iggled and ")
   `(chop "donkey")
   `(chop "bird")
   `(chop " was ")
   `(chop "goat")
   `(chop " swallow")
   `(chop "he_gthe") )

(de oldLady (Lst Flg)
   (loop
      (let C (pop 'Lst)
         (cond
            (Flg
               (setq Flg
                  (oldLady (get *Dict (- (char C) 94))) ) )
            ((= "_" C) (on Flg))
            ((= "/" C) (prinl))
            (T (prin C)) ) )
      (NIL Lst) )
   Flg )

(oldLady (car *Dict))

PL/M

100H:

/* CP/M CALL */
BDOS: PROCEDURE(FUNC, ARGS);
    DECLARE FUNC BYTE, ARGS ADDRESS;
    GO TO 5;
END BDOS;

/* PRINT STRING */
PRINT: PROCEDURE(STRING);
    DECLARE STRING ADDRESS;
    CALL BDOS(9, STRING);
END PRINT;

DECLARE COMMA$CRLF DATA (',',13,10,'$');
DECLARE CRLF DATA (13,10,'$');

DECLARE ANIMALS (8) ADDRESS;
ANIMALS(0) = .'FLY$';
ANIMALS(1) = .'SPIDER$';
ANIMALS(2) = .'BIRD$';
ANIMALS(3) = .'CAT$';
ANIMALS(4) = .'DOG$';
ANIMALS(5) = .'GOAT$';
ANIMALS(6) = .'COW$';
ANIMALS(7) = .'HORSE$';

DECLARE VERSES (8) ADDRESS;
VERSES(0) = .('I DON''T KNOW WHY SHE SWALLOWED THAT FLY',
              ' - PERHAPS SHE''LL DIE.',10,13,'$');
VERSES(1) = .'THAT WIGGLED AND JIGGLED AND TICKLED INSIDE HER$';
VERSES(2) = .'HOW ABSURD TO SWALLOW A BIRD$';
VERSES(3) = .'IMAGINED THAT - SHE SWALLOWED A CAT$';
VERSES(4) = .'WHAT A HOG TO SWALLOW A DOG$';
VERSES(5) = .'SHE JUST OPENED HER THROAT AND SWALLOWED THAT GOAT$';
VERSES(6) = .'I DON''T KNOW HOW SHE SWALLOWED THAT COW$';
VERSES(7) = .'SHE''S DEAD, OF COURSE.$';
 
DECLARE (I, J) BYTE;
DO I = 0 TO LAST(VERSES);
    CALL PRINT(.'THERE WAS AN OLD LADY WHO SWALLOWED A $');
    CALL PRINT(ANIMALS(I));
    CALL PRINT(.COMMA$CRLF);
    CALL PRINT(VERSES(I));
    CALL PRINT(.CRLF);
    
    J = I;
    DO WHILE J > 0 AND I < LAST(ANIMALS);
        CALL PRINT(.'SHE SWALLOWED THE $');
        CALL PRINT(ANIMALS(J));
        CALL PRINT(.' TO CATCH THE $');
        CALL PRINT(ANIMALS(J-1));
        CALL PRINT(.COMMA$CRLF);
        IF J <= 2 THEN DO;
            CALL PRINT(VERSES(J-1));
            CALL PRINT(.CRLF);
        END;
        J = J - 1;
    END;
END;

CALL BDOS(0,0);
EOF

PowerShell

$lines = @(
    'fly/'
    'spider/That wiggled and jiggled and tickled inside her,'
    'bird/How absurd, to swallow a bird,'
    'cat/Imagine that. She swallowed a cat,'
    'dog/What a hog to swallow a dog,'
    'goat/She just opened her throat and swallowed that goat,'
    'cow/I don''t know how she swallowed that cow,'
    'horse/She''s dead of course!'
)

$eatenThings = @()

for($i=0; $i -lt $lines.Count; $i++)
{
    $creature, $comment = $lines[$i].Split("/")
    $eatenThings += $creature

    "I know an old lady who swallowed a $creature,"
    
    if ($comment) {$comment}
    if ($i -eq ($lines.Count - 1)) {continue}
	
    for($j=$i; $j -ge 1; $j--)
    {
        "She swallowed the {0} to catch the {1}," -f $eatenThings[$j, ($j-1)]
    }

	"I don't know why she swallowed the fly."
	"Perhaps she'll die."
	""
}

Python

import zlib, base64

b64 = b'''
eNrtVE1rwzAMvedXaKdeRn7ENrb21rHCzmrs1m49K9gOJv9+cko/HBcGg0LHcpOfnq2np0QL
2FuKgBbICDAoeoiKwEc0hqIUgLAxfV0tQJCdhQM7qh68kheswKeBt5ROYetTemYMCC3rii//
WMS3WkhXVyuFAaLT261JuBWwu4iDbvYp1tYzHVS68VEIObwFgaDB0KizuFs38aSdqKv3TgcJ
uPYdn2B1opwIpeKE53qPftxRd88Y6uoVbdPzWxznrQ3ZUi3DudQ/bcELbevqM32iCIrj3IIh
W6plOJf6L6xaajZjzqW/qAsKIvITBGs9Nm3glboZzkVP5l6Y+0bHLnedD0CttIyrpEU5Kv7N
Mz3XkPBc/TSN3yxGiqMiipHRekycK0ZwMhM8jerGC9zuZaoTho3kMKSfJjLaF8v8wLzmXMqM
zJvGew/jnZPzclA08yAkikegDTTUMfzwDXBcwoE='''
print(zlib.decompress(base64.b64decode(b64)).decode("utf-8", "strict"))
animals = [
        ("fly", "I don't know why she swallowed a fly, perhaps she'll die."),
        ("spider", "It wiggled and jiggled and tickled inside her."),
        ("bird", "How absurd, to swallow a bird."),
        ("cat", "Imagine that, she swallowed a cat."),
        ("dog", "What a hog, to swallow a dog."),
        ("goat", "She just opened her throat and swallowed a goat."),
        ("cow", "I don't know how she swallowed a cow."),
        ("horse", "She's dead, of course.")]

for i, (animal, lyric) in enumerate(animals):
    print("There was an old lady who swallowed a {}.\n{}".format(animal, lyric))

    if animal == "horse": break

    for (predator, _), (prey, _) in zip(animals[i:0:-1], animals[i-1::-1]):
        print("\tShe swallowed the {} to catch the {}".format(predator, prey))

    if animal != "fly": print(animals[0][1])  # fly lyric
    print()  # new line

R

animals = list(
  c("fly", "I don't know why she swallowed a fly, perhaps she'll die."),
  c("spider", "It wiggled and jiggled and tickled inside her."),
  c("bird", "How absurd, to swallow a bird."),
  c("cat", "Imagine that, she swallowed a cat."),
  c("dog", "What a hog, to swallow a dog."),
  c("goat", "She just opened her throat and swallowed a goat."),
  c("cow", "I don't know how she swallowed a cow."),
  c("horse", "She's dead, of course.")
)

oldladyalive <- TRUE
oldladysnack <- 1

while(oldladyalive == TRUE) {
  nextmeal <- animals[[oldladysnack]][1]
  nextcomment <- animals[[oldladysnack]][2]
  print(sprintf("There was an old lady who swallowed a %s. %s",nextmeal,nextcomment))
  
  if(oldladysnack == 8){
    oldladyalive <- FALSE # she ate a horse :(
  } else if(oldladysnack > 1) {
    for(i in oldladysnack:2) {
      print(sprintf("    She swallowed the %s to catch the %s",
              animals[[i]][1], #e.g. spider (to catch the...
              animals[[i-1]][1])) # fly)
      
    }
    print(animals[[1]][2])
  }
  oldladysnack <- oldladysnack + 1
}

Racket

#lang at-exp racket

(define (line . xs) (for-each display xs) (newline))

(let loop ([animals
            '([fly #f]
              [spider "That wriggled and wiggled and tiggled inside her"]
              [bird   "How absurd to swallow a bird"]
              [cat    "Fancy that to swallow a cat"]
              [dog    "What a hog, to swallow a dog"]
              [cow    "I don't know how she swallowed a cow"]
              [horse  "She's dead, of course"])]
           [seen '()])
  (when (pair? animals)
    (match animals
      [(list (list animal desc) more ...)
       @line{There was an old lady that swallowed a @animal,}
       (when desc @line{@|desc|.})
       (when (pair? more)
         (for ([this (cons animal seen)] [that seen])
           @line{She swallowed the @this to catch the @that,})
         @line{I don't know why she swallowed a fly - perhaps she'll die!}
         @line{}
         (loop more (cons animal seen)))])))

Alternative solution:

#lang s-exp framework/private/decode
7VK7TsQwEOz9FcM1AcncZyCoQaLey/piCyuObJ+s/D3rXHj4lIIKgaCItJkZ7cyOfM0uTZ5m
7J6siQaFEmhE8AxPPCNbykiFvA/FMAhHP2v1AA5jl/EyhoJiZyRrLlW4xWSipSlVtvMe7MyV
Ul/0SZNjE7XIhSjRDYOv+Mgon+a8zm5MIoes3qvHJkuuf8su5ICecm8X7LvuOLjIWt3Lfjqk
U+SaYuVXditxxdu8b338rOvEUas7GvuVa44Tcuu2/qz7CHuu6PeWwGHQ6rmiBCtz24KwWy0I
3KZdqvwDbfWhXPhY+S59RLX5dkTapF66/2/3fYMNMZklVJfAhlgjHKW2k8B7tbtRrw==

Raku

(formerly Perl 6)

my @victims =
    fly    => "  I don't know why S—",
    spider => "  That wriggled and jiggled and tickled inside her.",
    bird   => "  How absurd, T!",
    cat    => "  Fancy that, S!",
    dog    => "  What a hog, T!",
    goat   => "  She just opened her throat, and in walked the goat!",
    cow    => "  I don't know how S!",
    horse  => "  She's dead, of course...";

my @history = "I guess she'll die...\n";

for (flat @victims».kv) -> $victim, $_ is copy {
    say "There was an old lady who swallowed a $victim...";

    s/ «S» /she swallowed the $victim/;
    s/ «T» /to swallow a $victim!/;
    .say;
    last when /dead/;

    @history[0] ~~ s/^X/She swallowed the $victim/;
    .say for @history;
    @history.unshift($_) if @history < 5;
    @history.unshift("X to catch the $victim,");
}

And that's how I larned it!

REXX

/*REXX program displays  song lyrics  for:   "I Know an Old Lady who Swallowed a Fly".  */
sw= 79                                           /*the width of the terminal screen, -1.*/
@.=;            @.1 = "I don't know why she swallowed a fly,"
                @.2 = "That wriggled and jiggled and tickled inside her.";    @.2.0=.
                @.3 = "How absurd to swallow a bird!"
                @.4 = "Imagine that, to swallow a cat!"
                @.5 = "My, what a hog, to swallow a dog!"
                @.6 = "Just opened her throat and swallowed a goat!"
                @.7 = "I wonder how she swallowed a cow?!"
                @.8 = "She's dead, of course!!"
$ = 'fly spider bird cat dog goat cow horse'
#= words($)                                      /*#:  number of animals to be swallowed*/

  do j=1  for #;        say
  say center('I know an old lady who swallowed a'     word($, j)",",  sw)
  if j\==1  then  say center(@.j, sw)
  if j ==#  then leave                           /*Is this the last verse?   We're done.*/
                      do k=j  to 2  by -1;      km= k-1;              ??= word($, km)','
                      say center('She swallowed the'   word($,k)  "to catch the"   ??, sw)
                      if @.km.0\==''  then say center(@.km, sw)
                      end   /*k*/                /* [↑]  display the lyrics of the song.*/
  say center(@.1, sw)
  say center("I guess she'll die.", sw)
  end   /*j*/                                    /*stick a fork in it,  we're all done. */
output   (with the lyrics being centered):
                    I know an old lady who swallowed a fly,
                     I don't know why she swallowed a fly,
                              I guess she'll die.

                  I know an old lady who swallowed a spider,
               That wriggled and jiggled and tickled inside her.
                  She swallowed the spider to catch the fly,
                     I don't know why she swallowed a fly,
                              I guess she'll die.

                   I know an old lady who swallowed a bird,
                         How absurd to swallow a bird!
                  She swallowed the bird to catch the spider,
               That wriggled and jiggled and tickled inside her.
                  She swallowed the spider to catch the fly,
                     I don't know why she swallowed a fly,
                              I guess she'll die.

                    I know an old lady who swallowed a cat,
                        Imagine that, to swallow a cat!
                   She swallowed the cat to catch the bird,
                  She swallowed the bird to catch the spider,
               That wriggled and jiggled and tickled inside her.
                  She swallowed the spider to catch the fly,
                     I don't know why she swallowed a fly,
                              I guess she'll die.

                    I know an old lady who swallowed a dog,
                       My, what a hog, to swallow a dog!
                    She swallowed the dog to catch the cat,
                   She swallowed the cat to catch the bird,
                  She swallowed the bird to catch the spider,
               That wriggled and jiggled and tickled inside her.
                  She swallowed the spider to catch the fly,
                     I don't know why she swallowed a fly,
                              I guess she'll die.

                   I know an old lady who swallowed a goat,
                 Just opened her throat and swallowed a goat!
                   She swallowed the goat to catch the dog,
                    She swallowed the dog to catch the cat,
                   She swallowed the cat to catch the bird,
                  She swallowed the bird to catch the spider,
               That wriggled and jiggled and tickled inside her.
                  She swallowed the spider to catch the fly,
                     I don't know why she swallowed a fly,
                              I guess she'll die.

                    I know an old lady who swallowed a cow,
                      I wonder how she swallowed a cow?!
                   She swallowed the cow to catch the goat,
                   She swallowed the goat to catch the dog,
                    She swallowed the dog to catch the cat,
                   She swallowed the cat to catch the bird,
                  She swallowed the bird to catch the spider,
               That wriggled and jiggled and tickled inside her.
                  She swallowed the spider to catch the fly,
                     I don't know why she swallowed a fly,
                              I guess she'll die.

                   I know an old lady who swallowed a horse,
                            She's dead, of course!!

Ruby

descriptions = {
  :fly    => "I don't know why S",
  :spider => "That wriggled and jiggled and tickled inside her.",
  :bird   => "Quite absurd T",
  :cat    => "Fancy that, S",
  :dog    => "What a hog, S",
  :goat   => "She opened her throat T",
  :cow    => "I don't know how S",
  :horse  => "She's dead, of course.",
}
animals = descriptions.keys

animals.each_with_index do |animal, idx|
  puts "There was an old lady who swallowed a #{animal}."

  d = descriptions[animal]
  case d[-1]
  when "S" then d[-1] = "she swallowed a #{animal}."
  when "T" then d[-1] = "to swallow a #{animal}."
  end
  puts d
  break if animal == :horse

  idx.downto(1) do |i|
    puts "She swallowed the #{animals[i]} to catch the #{animals[i-1]}."
    case animals[i-1]
    when :spider, :fly then puts descriptions[animals[i-1]]
    end
  end

  print "Perhaps she'll die.\n\n"
end

Rust

Rust Playground

enum Action {Once, Every, Die}
use Action::*;

fn main() {
    let animals = [ ("horse" , Die  , "She's dead, of course!")
                  , ("donkey", Once , "It was rather wonky. To swallow a donkey.")
                  , ("cow"   , Once , "I don't know how. To swallow a cow.")
                  , ("goat"  , Once , "She just opened her throat. To swallow a goat.")
                  , ("pig"   , Once , "Her mouth was so big. To swallow a pig.")
                  , ("dog"   , Once , "What a hog. To swallow a dog.")
                  , ("cat"   , Once , "Fancy that. To swallow a cat.")
                  , ("bird"  , Once , "Quite absurd. To swallow a bird.")
                  , ("spider", Once , "That wriggled and jiggled and tickled inside her.")
                  , ("fly"   , Every, "I don't know why she swallowed the fly.")
                  ];

    for (i, a) in animals.iter().enumerate().rev() {
        println!("There was an old lady who swallowed a {}\n{}", a.0, a.2);

        if let Die = a.1 {break}

        for (swallowed, to_catch) in animals[i..].iter().zip(&animals[i+1..]) {
            println!("She swallowed the {} to catch the {}.", swallowed.0, to_catch.0);

            if let Every = to_catch.1 {
                println!("{}", to_catch.2);
            }
        }

        println!("Perhaps she'll die.\n");
    }
}

Scala

case class Verse(animal: String, remark: String, die: Boolean = false, always: Boolean = false)

val verses = List(
  Verse("horse", "She’s dead, of course!", die = true),
  Verse("donkey", "It was rather wonky. To swallow a donkey."),
  Verse("cow", "I don’t know how. To swallow a cow."),
  Verse("goat", "She just opened her throat. To swallow a goat."),
  Verse("pig", "Her mouth was so big. To swallow a pig."),
  Verse("dog", "What a hog. To swallow a dog."),
  Verse("cat", "Fancy that. To swallow a cat."),
  Verse("bird", "Quite absurd. To swallow a bird."),
  Verse("spider", "That wriggled and jiggled and tickled inside her."),
  Verse("fly", "I don’t know why she swallowed the fly.", always = true)
)

for (i <- 1 to verses.size; verse = verses takeRight i; starting = verse.head) {
  println(s"There was an old lady who swallowed a ${starting.animal},")
  println(starting.remark)
  if (!starting.die) {
    for (List(it, next) <- verse.sliding(2,1)) {
      println(s"She swallowed the ${it.animal} to catch the ${next.animal},")
      if (next.always) println(next.remark)
    }
    println("Perhaps she’ll die!")
    println
  }
}
Output:
There was an old lady who swallowed a fly,
I don’t know why she swallowed the fly.
Perhaps she’ll die!

There was an old lady who swallowed a spider,
That wriggled and jiggled and tickled inside her.
She swallowed the spider to catch the fly,
I don’t know why she swallowed the fly.
Perhaps she’ll die!

There was an old lady who swallowed a bird,
Quite absurd. To swallow a bird.
She swallowed the bird to catch the spider,
She swallowed the spider to catch the fly,
I don’t know why she swallowed the fly.
Perhaps she’ll die!

...

There was an old lady who swallowed a horse,
She’s dead, of course!

Scratch

See https://scratch.mit.edu/projects/192324257/.

Seed7

$ include "seed7_05.s7i";

const array array string: verses is [] (
    [] ("fly", "I don't know why she swallowed the fly."),
    [] ("spider", "That wriggled and jiggled and tickled inside her."),
    [] ("bird", "Quite absurd. To swallow a bird."),
    [] ("cat", "Fancy that. To swallow a cat."),
    [] ("dog", "What a hog. To swallow a dog."),
    [] ("pig", "Her mouth was so big. To swallow a pig."),
    [] ("goat", "She just opened her throat. To swallow a goat."),
    [] ("cow", "I don't know how. To swallow a cow."),
    [] ("donkey", "It was rather wonky. To swallow a donkey."),
    [] ("horse", "She's dead, of course!"));

const proc: main is func
  local
    var integer: verseNumber is 0;
    var integer: animal is 0;
  begin
    for key verseNumber range verses do
      writeln("There was an old lady who swallowed a " <& verses[verseNumber][1] <& ",");
      writeln(verses[verseNumber][2]);
      if verseNumber <> length(verses) then
        for animal range verseNumber downto 2 do
          writeln("She swallowed the " <& verses[animal][1] <& " to catch the " <& verses[pred(animal)][1] <& ",");
        end for;
        if verseNumber <> 1 then
          writeln(verses[1][2]);
        end if;
        writeln("Perhaps she'll die!");
        writeln;
      end if;
    end for;
  end func;

Sidef

Translation of: Raku
var victims = [
    :fly:    "  I don't know why S—",
    :spider: "  That wriggled and jiggled and tickled inside her.",
    :bird:   "  How absurd, T!",
    :cat:    "  Fancy that, S!",
    :dog:    "  What a hog, T!",
    :goat:   "  She just opened her throat, and in walked the goat!",
    :cow:    "  I don't know how S!",
    :horse:  "  She's dead, of course...",
];

var history = ["I guess she'll die...\n"];

victims.each { |pair|
    var (victim, verse) = pair...;
    say "There was an old lady who swallowed a #{victim}...";

    verse.sub!(/\bS\b/, "she swallowed the #{victim}");
    verse.sub!(/\bT\b/, "to swallow a #{victim}!");

    say verse;
    verse ~~ /dead/ && break;

    history[0].sub!(/^X/, "She swallowed the #{victim}");
    history.each{.say};
    history.len < 5 && history.unshift(verse);
    history.unshift("X to catch the #{victim},");
};

Tcl

Because the song is highly repetitive, it compresses wonderfully.

package require Tcl 8.6

puts [zlib inflate [binary decode base64 "
    7VRNa8MwDL3nV2inXkZ+xDa29taxws5q7NZuPSvYDib/fnJKPxwXBoNCx3KTn56t
    p6dEC9hbioAWyAgwKHqIisBHNIaiFICwMX1dLUCQnYUDO6oevJIXrMCngbeUTmHr
    U3pmDAgt64ov/1jEt1pIV1crhQGi09utSbgVsLuIg272KdbWMx1UuvFRCDm8BYGg
    wdCos7hbN/Gknair904HCbj2HZ9gdaKcCKXihOd6j37cUXfPGOrqFW3T81sc560N
    2VItw7nUP23BC23r6jN9ogiK49yCIVuqZTiX+i+sWmo2Y86lv6gLCiLyEwRrPTZt
    4JW6Gc5FT+ZemPtGxy53nQ9ArbSMq6RFOSr+zTM915DwXP00jd8sRoqjIoqR0XpM
    nCtGcDITPI3qxgvc7mWqE4aN5DCknyYy2hfL/MC85lzKjMybxnsP452T83JQNPMg
    JIpHoA001DH88A0=
"]]

TXR

Here is somewhat verbose program showing a different approach.

The idea is to start with the last two verses of the song, and then work backwards to produce the earlier verses. This is done by recursively pattern matching on the song to extract text and produce the earlier verse, which is then prepended to the song.

The later verse does not contain one key piece of information we need to produce the prior verse: the animal-specific answer line for the prior animal. So we look this up by scanning a text which serves as a table.

The recursion terminates when the second pattern case matches the first verse: the third line is "Perhaps she'll die". In this case the song is not lengthened any more, and a terminating flag variable is bound to true.

Note one detail: in the first verse we have "... don't know why she swallowed the fly". But in subsequent verses it is "that fly" not "the fly". So we do a lookup on the fly also to substitute the appropriate line, and in the fly case we skip the original line (see the first @(maybe)).

@(deffilter abbr
   ("IK" "I know an old lady who swallowed a") ("SW" "She swallowed the")
   ("SS" "she swallowed") ("CA" "to catch the") ("XX" "Perhaps she'll die")
   ("C" "cow") ("G" "goat") ("D" "dog") ("@" "cat") ("R" "bird")
   ("$" "spider") ("F" "fly"))
@(bind lastverse
   ("IK C"
    "I don't know how SS the C"
    "SW C CA G"
    "SW G CA D"
    "SW D CA @"
    "SW @ CA R"
    "SW R CA $"
    "SW $ CA F"
    "But I don't know why SS that F"
    "XX"
    ""
    "IK horse"
    "She's alive and well of course!"))
@(bind animal_line
  ("G: Opened her throat and down went the G!"
   "D: What a hog to swallow a D!"
   "@: Imagine that! She swallowed a @!"
   "R: How absurd to swallow a R!"
   "$: That wriggled and jiggled and tickled inside her"
   "F: But I don't know why SS the F"))
@(define expand_backwards (song lengthened_song done))
@  (local line2 line3 verse rest animal previous_animal previous_animal_verse)
@  (next :list song)
@  (cases)
IK @animal
@line2
SW @animal CA @previous_animal
@    (maybe)
But @(skip)F
@    (end)
@    (collect)
@    verse
@    (until)

@    (end)
@    (collect)
@    rest
@    (end)
@    (next :list animal_line)
@    (skip)
@previous_animal: @previous_animal_verse
@    (output :into lengthened_song)
IK @previous_animal
@previous_animal_verse
@      (repeat)
@      verse
@      (end)

@      (repeat)
@      song
@      (end)
@    (end)
@    (bind done nil)
@ (or)
IK @(skip)
@line2
XX
@    (bind lengthened_song song)
@    (bind done t)
@ (end)
@(end)
@(define expand_song (in out))
@  (local lengthened done)
@  (expand_backwards in lengthened done)
@  (cases)
@    (bind done nil)
@    (expand_song lengthened out)
@  (or)
@    (bind out lengthened)
@  (end)
@(end)
@(expand_song lastverse song)
@(output :filter abbr)
@  (repeat)
@song
@  (end)
@(end)

UNIX Shell

Works with: Bash
animals=(fly spider bird cat dog pig goat cow donkey horse)
comments=("I don't know why she swallowed that fly"
          "That wriggled and jiggled and tickled inside her"
          "Quite absurd, to swallow a bird"
          "How about that, to swallow a cat"
          "What a hog, to swallow a dog"
          "Her mouth was so big to swallow a pig"
          "She just opened her throat to swallow a goat."
          "I don't know how she swallowed a cow."
          "It was rather wonky to swallow a donkey"
          "She's dead, of course!")
include=(2 2 1 1 1 1 1 1 1 0)

for (( i=0; i<${#animals[@]}; ++i )); do
   echo "There was an old lady who swallowed a ${animals[i]}"
   echo "${comments[i]}"
   if (( include[i] )); then
     if (( i )); then
       for (( j=i-1; j>=0; --j )); do
         echo "She swallowed the ${animals[j+1]} to catch the ${animals[j]}"
         if (( include[j] > 1 )); then
           echo "${comments[j]}"
         fi
       done
     fi
     echo "Perhaps she'll die"
     echo
   fi
done

Ursa

Translation of: C#
decl string<> reason creatures comments
append "She swallowed the " " to catch the " reason
append "fly" "spider" "bird" "cat" "dog" "goat" "cow" "horse" creatures
append "I don't know why she swallowed that fly.\nPerhaps she'll die\n" comments
append "That wiggled and jiggled and tickled inside her" comments
append "How absurd, to swallow a bird" comments
append "Imagine that. She swallowed a cat" comments
append "What a hog to swallow a dog" comments
append "She just opened her throat and swallowed that goat" comments
append "I don't know how she swallowed that cow" comments
append "She's dead of course" comments

decl int max
set max (size creatures)
for (decl int i) (< i max) (inc i)
        out "There was an old lady who swallowed a " creatures<i> endl console
        out comments<i> endl console
        decl int j
        for (set j i) (and (> j 0) (< i (- max 1))) (dec j)
                out reason<0> creatures<j> reason<1> creatures<(int (- j 1))> endl console
                if (= j 1)
                        out comments<(int (- j 1))> endl console
                end if
        end for
end for
in string console

VBScript

a=array( _
array("fly",""),_ 
array("spider","That wiggled and jiggled and tickled inside her"), _
array("bird","How absurd, to swallow a bird"), _
array("cat","Imagine that. She swallowed a cat"), _
array("dog","What a hog to swallow a dog"), _
array("goat","She just opened her throat and swallowed that goat"),_ 
array("cow","I don't know how she swallowed that cow"), _
array("horse","She's dead of course...")_ 
)

b1="I don't know why she swallowed the fly." & vbcrlf &"Perhaps she'll die."& vbcrlf
b2="There was an old lady who swallowed a @ani@."
b3="She swallowed the @ani@ to catch the @pani@."

sub print(s): wscript.stdout.write(s) & vbcrlf : end sub 

for i=0 to ubound(a)
     ani=a(i)(0)
     print replace(b2,"@ani@",ani)
     print a(i)(1)
     if i=ubound(a) then exit for  'horse
   for j= i-1 to 0 step -1
      oldani=ani
      ani=a(j)(0)
      print replace(replace(b3,"@ani@",oldani),"@pani@",ani)
      if j=1 then print a(1)(1) ' spider
   next 
   print b1
next

V (Vlang)

const (
    name = 0
    lyric = 1
    animals = [
            ["fly", "I don't know why she swallowed a fly. Perhaps she'll die."],
            ["spider", "That wiggled and jiggled and tickled inside her."],
            ["bird", "How absurd, to swallow a bird."],
            ["cat", "Imagine that, she swallowed a cat."],
            ["dog", "What a hog, to swallow a dog."],
            ["goat", "She just opened her throat and swallowed that goat."],
            ["cow", "I don't know how she swallowed that cow."],
            ["horse", "She's dead, of course."],
        ]
)
 
fn main() {
    for i, animal in animals {
        println("There was an old lady who swallowed a ${animal[name]},")
        if i > 0 {
            println(animal[lyric])
        }
        // Swallowing the last animal signals her death, cutting the
        //  lyrics short.
        if i+1 == animals.len {
            break
        }
        for j := i; j > 0; j-- {
            println("She swallowed the ${animals[j][name]} to catch the ${animals[j-1][name]},")
        }
        println("${animals[0][lyric]}\n")
    }
}
Output:
There was an old lady who swallowed a fly,
I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a spider,
That wiggled and jiggled and tickled inside her.
She swallowed the spider to catch the fly,
I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a bird,
How absurd, to swallow a bird.
She swallowed the bird to catch the spider,
She swallowed the spider to catch the fly,
I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a cat,
Imagine that, she swallowed a cat.
She swallowed the cat to catch the bird,
She swallowed the bird to catch the spider,
She swallowed the spider to catch the fly,
I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a dog,
What a hog, to swallow a dog.
She swallowed the dog to catch the cat,
She swallowed the cat to catch the bird,
She swallowed the bird to catch the spider,
She swallowed the spider to catch the fly,
I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a goat,
She just opened her throat and swallowed that goat.
She swallowed the goat to catch the dog,
She swallowed the dog to catch the cat,
She swallowed the cat to catch the bird,
She swallowed the bird to catch the spider,
She swallowed the spider to catch the fly,
I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a cow,
I don't know how she swallowed that cow.
She swallowed the cow to catch the goat,
She swallowed the goat to catch the dog,
She swallowed the dog to catch the cat,
She swallowed the cat to catch the bird,
She swallowed the bird to catch the spider,
She swallowed the spider to catch the fly,
I don't know why she swallowed a fly. Perhaps she'll die.

There was an old lady who swallowed a horse,
She's dead, of course.

Wren

Translation of: Kotlin
var animals = ["fly", "spider", "bird", "cat","dog", "goat", "cow", "horse"]

var phrases = [
    "",
    "That wriggled and jiggled and tickled inside her",
    "How absurd to swallow a bird",
    "Fancy that to swallow a cat",
    "What a hog, to swallow a dog",
    "She just opened her throat and swallowed a goat",
    "I don't know how she swallowed a cow",
    "\n  ...She's dead of course"
]

var sing = Fn.new {
     for (i in 0..7) {
       System.print("There was an old lady who swallowed a %(animals[i]);")
       if (i > 0) System.print("%(phrases[i])!")
       if (i == 7) return
       System.print()
       if (i > 0) {
           for (j in i..1) {
               System.write("  She swallowed the %(animals[j]) to catch the %(animals[j - 1])")
               System.print((j < 3) ? ";" :",")
               if (j == 2) System.print("  %(phrases[1])!")
           }
       }
       System.print("  I don't know why she swallowed a fly - Perhaps she'll die!\n")
    }
}

sing.call()

XPL0

Translation of: C
include xpllib; \For Print

int Animals, Verses, I, J;
[Animals:= ["fly", "spider", "bird", "cat", "dog", "goat", "cow", "horse"];
Verses:= [
    "I don't know why she swallowed that fly.^m^jPerhaps she'll die^m^j",
    "That wiggled and jiggled and tickled inside her",
    "How absurd, to swallow a bird",
    "Imagine that. She swallowed a cat",
    "What a hog to swallow a dog",
    "She just opened her throat and swallowed that goat",
    "I don't know how she swallowed that cow",
    "She's dead of course" ];
for I:= 0 to 8-1 do
    [Print("There was an old lady who swallowed a %s\n%s\n", Animals(I), Verses(I));
    J:= I;
    while J > 0 and I < 8-1 do
        [Print("She swallowed the %s to catch the %s\n", Animals(J), Animals(J-1));
        if J = 1 then Print("%s\n", Verses(0));
        J:= J-1;
        ]
    ]
]

Z80 Assembly

Copy this into WinApe's built-in assembler, press Ctrl+F9 to assemble, then type CALL &8000 into the BASIC terminal to see the output. (Remember that WinApe uses pure ASCII meaning that Shift+6 on your keyboard is the & symbol!) Press any key to print each verse. After the last verse, press any key to return to BASIC.

waitChar equ &BB06
PrintChar equ &BB5A

org &8000

	ld ix,VerseTable
	ld iy,OldLadyLookup
	ld b,8                 ;8 verses total


outerloop_song:
	    push bc
		    ld a,(ix+0)
		    ld c,a        ;get the low byte of verse ptr
		    ld a,(ix+1)
		    ld b,a        ;get the high byte
		    ;bc = the memory location of Verse1
		    call loop_meta_PrintString
		    inc ix
		    inc ix  ;next verse
	    pop bc

	    call WaitChar   ;wait for user to press any key before continuing so they
                            ;    have time to read it.

	djnz outerloop_song

ReturnToBasic:
		ret		
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; SUBROUTINES ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
loop_meta_PrintString:
		ld a,(bc)
		or a		;compare A to 0. 0 is the null terminator for verses.
		ret z
		cp 255		;255 means "goto the verse specified after the 255"
		jr z,GotoPreviousVerse
		ld (smc_loop_meta_PrintString_alpha+2),a
		;use self modifying code to point IY's offset to the correct 
		;	song line, without changing IY itself.
		inc a
		ld (smc_loop_meta_PrintString_beta+2),a
smc_loop_meta_PrintString_alpha:
		ld a,(iy+0)	;the "+0" gets clobbered with the desired lyric low byte
		ld L,a
smc_loop_meta_PrintString_beta:
		ld a,(iy+0)	;the "+0" gets clobbered with the desired lyric high byte
		ld H,a
		call PrintString	;now print the string in HL.
		inc bc
		jp loop_meta_PrintString
;;;;;;;;;;;;;;;;;;;;;;;	
GotoPreviousVerse:
	inc bc		;advance past &FF opcode
	ld a,(bc)       ;get low byte
	ld e,a
	inc bc		;advance to high byte
	ld a,(bc)
	ld d,a
	push de
	pop bc
	inc bc		;advance past "There was an old lady who..."
	jp loop_meta_PrintString
	
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;	
PrintString:
	ld a,(hl)
	or a
	ret z
	call PrintChar
	inc hl
	jr PrintString

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;	DATA     ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
VerseTable:
	word Verse1,Verse2,Verse3,Verse4,Verse5,Verse6,Verse7,Verse8
Verse1:
	byte 2,4,40,6,40,0				;fly
Verse2:
	byte 2,8,40,10,40,36,8,38,255			;spider
	word Verse1
Verse3:
	byte 2,12,40,14,40,36,12,38,255			;bird
	word Verse2
Verse4:
	byte 2,16,40,18,40,36,16,38,255			;cat
	word Verse3
Verse5:
	byte 2,20,40,22,40,36,20,38,255			;dog
	word Verse4
Verse6:
	byte 2,24,40,26,40,36,24,38,255			;goat
	word Verse5
Verse7:
	byte 2,28,40,30,40,36,28,38,255			;cow
	word Verse6
Verse8:
	byte 2,32,40,34,0				;horse

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;	 

OldLadyLookup:
		word null		;0
		word OldLady		;2
		word Fly		;4
		word Fly2		;6
		word Spider		;8
		
		word Spider2		;10
		word Bird		;12
		word Bird2		;14
		word Cat		;16
		word Cat2		;18
		
		word Dog		;20
		word Dog2		;22
		word Goat		;24
		word Goat2		;26
		word Cow		;28
		
		word Cow2		;30
		word Horse		;32
		word Horse2		;34
		word Catch1		;36
		word Catch2		;38
		
		word Song_NewLine	;40

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;		
null:
		byte 0
OldLady:
		byte "There was an old lady who swallowed a ",0
Fly:
		byte "fly",0
Fly2:
		byte "I don't know why she swallowed a fly, perhaps she'll die.",0
Spider:
       		byte "spider",0
Spider2:
		byte "It wiggled and jiggled and tickled inside her.",0
Bird:
        	byte "bird",0
Bird2:
		byte "How absurd, to swallow a bird.",0
Cat:
        	byte "cat",0
Cat2:
		byte "Imagine that, she swallowed a cat.",0
Dog:
       		byte "dog",0
Dog2:
		byte "What a hog, to swallow a dog.",0
Goat:
        	byte "goat",0
Goat2:
		byte "She just opened her throat and swallowed a goat.",0
Cow:
        	byte "cow",0
Cow2:
		byte "I don't know how she swallowed a cow.",0
Horse:
        	byte "horse",0
Horse2:
		byte "She's dead, of course.",0
Catch1:	
		byte "She swallowed the ",0
Catch2:
		byte " to catch the ",0
Song_NewLine:
		byte 13,10,0		;control codes for a new line.

zkl

Translation of: Tcl

Uncompresses the base64 encoded gziped text of the song. Uses shared libraries zlib and msg hashing for the codecs.

var ZLib=Import("zeelib"), MsgHash=Import("zklMsgHash");
text:=
  "eJztlE1uwyAQhdflFOOVNyhXyLap1FV7AWKIoaFMBFjIt++M7YVpLfVHilQp2cHMg3l8T+IA"
  "54AFVAD0GrzSIxSLkIryHovRoODkRykOoDG0eVYXO0KyZqXKtFt0/WBS4nbrPWhndoKK3w5J"
  "F6dNlA/i1aoMJbq+99wIGt5W6+y6M69dSKQHa+JOvHxxMl8GGaFTubNrd9d9xdFFLcUjq45p"
  "iJotLP2l22zY5XptdqHxaxjyP8GgcXT4XfUuGLqNdjUO6m/RoHJtdoZ6M9g09lI8j5Ia9AoF"
  "lvY1OFJsgaNybXcK4LYA/4Bvj4zlaUgZ8GIC1SzbsBEZN9n/LN5izfXa+hTbPZQ/fxZY+HDB"
  "wPMtqesBk2K/+V+QtvI7B3zP7OqZWYzJTI7aBNooLQFPlMdA5aYRH3dS5jc=";

MsgHash.base64decode(text) : 
ZLib.Inflator().write(_).close().read().text.println();
Output:
I know an old lady who swallowed a fly,
I don't know why she swallowed the fly,
I guess she'll die.
...
I know an old lady who swallowed a horse,
She's dead, of course!!