Old lady swallowed a fly: Difference between revisions

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m (→‎{{header|Haskell}}: Minor tweaks - mainly importing only tails, rather than whole Data.List library)
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{{Works with|GHC|7.8.3}}
{{Works with|GHC|7.8.3}}


<lang haskell>#!/usr/bin/env runhaskell
<lang haskell>import Data.List (tails)

import Data.List


-- Once means the phrase is only printed in the verse about that animal.
-- Once means the phrase is only printed in the verse about that animal.
Line 934: Line 932:
-- Die is only used for the horse, and means the chain of animals won't be
-- Die is only used for the horse, and means the chain of animals won't be
-- included in the verse.
-- included in the verse.
data AnimalAction = Once | Every | Die
data AnimalAction
= Once
| Every
| Die


animals =
animals = [("horse", Die, "She's dead, of course!"),
("donkey", Once, "It was rather wonky. To swallow a donkey."),
[ ("horse", Die, "She's dead, of course!")
("cow", Once, "I don't know how. To swallow a cow."),
, ("donkey", Once, "It was rather wonky. To swallow a donkey.")
("goat", Once, "She just opened her throat. To swallow a goat."),
, ("cow", Once, "I don't know how. To swallow a cow.")
("pig", Once, "Her mouth was so big. To swallow a pig."),
, ("goat", Once, "She just opened her throat. To swallow a goat.")
("dog", Once, "What a hog. To swallow a dog."),
, ("pig", Once, "Her mouth was so big. To swallow a pig.")
("cat", Once, "Fancy that. To swallow a cat."),
, ("dog", Once, "What a hog. To swallow a dog.")
("bird", Once, "Quite absurd. To swallow a bird."),
, ("cat", Once, "Fancy that. To swallow a cat.")
("spider", Once, "That wriggled and jiggled and tickled inside her."),
, ("bird", Once, "Quite absurd. To swallow a bird.")
("fly", Every, "I don't know why she swallowed the fly.")]
, ("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 :: [(String, AnimalAction, String)] -> [String]
verse ((anim, act, phrase):restAnims) =
verse ((anim, act, phrase):restAnims) =
let lns = ["I know an old lady who swallowed a " ++ anim ++ ".", phrase]
let lns = ["I know an old lady who swallowed a " ++ anim ++ ".", phrase]
in case act of Die -> lns
in case act of
_ -> lns ++ verse' restAnims anim
Die -> lns
_ -> lns ++ verse' restAnims anim


verse' :: [(String, AnimalAction, String)] -> String -> [String]
verse' :: [(String, AnimalAction, String)] -> String -> [String]
Line 957: Line 961:
verse' ((anim, act, phrase):restAnims) prevAnim =
verse' ((anim, act, phrase):restAnims) prevAnim =
let why = "She swallowed the " ++ prevAnim ++ " to catch the " ++ anim ++ "."
let why = "She swallowed the " ++ prevAnim ++ " to catch the " ++ anim ++ "."
lns = case act of Every -> [why, phrase]
lns =
_ -> [why]
case act of
Every -> [why, phrase]
_ -> [why]
in lns ++ verse' restAnims anim
in lns ++ verse' restAnims anim


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


main :: IO ()
main = putStr $ unlines song</lang>
main = putStr $ unlines song</lang>


Revision as of 19:16, 3 January 2017

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.


Related task



Ada

<lang 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;</lang>

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.

<lang algol68>#!/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!")</lang>

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.

<lang algol68>#!/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</lang>

AutoHotkey

Works with: AutoHotkey 1.1

<lang AutoHotkey>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</lang>

AWK

<lang AWK>

  1. 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)

} </lang>

Babel

<lang 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"      " "))))

</lang>

Batch File

<lang dos>@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</lang>

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.

<lang befunge>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!|</lang>

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. <lang bbcbasic>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</lang>

C

<lang 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"

};

  1. 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]);
           }
       }
   }

}</lang>

C#

<lang csharp>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();
       }
   }

}</lang>

COBOL

<lang 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.

</lang>

Common Lisp

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

<lang lisp>(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. ~%~%"))))))</lang>
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!

D

Translation of: C

<lang d>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;

}</lang>

A more structured alternative version: <lang d>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;
   }

}</lang>

Elena

<lang elena>#import system.

  1. import extensions.
  1. symbol Creatures = ("fly", "spider", "bird", "cat", "dog", "goat", "cow", "horse").
  2. symbol Comments =

( 

           "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"

).

  1. symbol program =

[ 

   0 till:(Creatures length) &doEach: i
   [
       console
           writeLine:"There was an old lady who swallowed a {0}" &args:(Creatures@i)
           writeLine:(Comments@i).
       
       ((i != 0)&&(i != Creatures length - 1))?
       [
           i till:0 &by:1 &doEach:j
           [
               console writeLine:"She swallowed the {0} to catch the {1}" &args:(Creatures@j):(Creatures@(j - 1)).
           ].
           
           console writeLine:(Comments@0).
       ].
           
       console writeLine.            
   ].

]. </lang>

Elixir

Translation of: Ruby

<lang elixir>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</lang>

Factor

Windows users should put zlib1.dll[1] to factor folder. <lang factor>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</lang>

Forth

swallow-addr is obviously a good candidate for an object, but Forth has many OO candidates - we won't settle that argument here. <lang forth>: 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!" ;</lang>

Frege

Translation of: Haskell
Works with: Frege version 3.23.888-g4e22ab6

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

<lang frege>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</lang>

Go

Go Playground <lang go>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 {
           fmt.Printf("She swallowed the %s to catch the %s,\n", animals[i][name], animals[i-1][name])
           i--
       }

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

}</lang>

Haskell

Works with: GHC version 7.8.3

<lang haskell>import Data.List (tails)

-- 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 :: IO () main = putStr $ unlines song</lang>

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. <lang Icon>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</lang> Sample output omitted.

Library: Icon Programming Library

printf.icn provides printf formatting

J

This defines T to be the required text. <lang j>T=: e=:3 :'T=:T,y,LF' E=:e@,&'.' O=:'I know an old lady who swallowed a 'E@,] I=:e bind('I dont know why she swallowed the fly.',LF,'Perhaps shell 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 dont know how' 'Donkey'N'It was rather wonky' O'Horse' e'Shes dead, of course!'</lang>

Java

Translation of C via D <lang java>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);
   }

}</lang>

Liberty BASIC

<lang lb> '[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 </lang>

<lang logo>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</lang>

Maple

<lang 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;</lang>

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

<lang Mathematica>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]) <> notes9] & /@ Range[8])];</lang>
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.

Nim

Translation of: Python

<lang nim>import zlib, base64

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

proc uncompress*(source: string, destLen: var int): string = 

 result = newString(destLen)
 discard uncompress(result.cstring, addr destLen, source.cstring, source.len)

var length = 10_000 echo b64.decode.uncompress length</lang>

OCaml

Using a dictionary

Only one minimalist line of code (the last line): <lang ocaml>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</lang>

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: <lang ocaml>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</lang>

Using Logic

<lang ocaml>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!"</lang>

Perl

Using string subst:<lang perl>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; }</lang> Using compression: (Assumes a Unix-like OS and the availability of the uudecode and bunzip2 utilities). <lang perl>open OUT, "| uudecode | bunzip2" and print OUT and close OUT;

__DATA__ begin-base64 644 - QlpoOTFBWSZTWUSbX/0AAZRfgAAQYIUACBFgbIA//96gQAK9oAAAxhMTQYIx DIwmDEoAAAAAAxhMTQYIxDIwmBSkiNIaJtCCAzJPU1G4ueVmGZMsMzBz0N5v hr4j29SRSSCZgyv8BDAAdOE3oFIFIhMAQMtm2Zy/MbRs9U1pgzCzGcaGnTYN u5NJ+/D4TfkcZZ39PmNJuN8rxjMrJTfvr8rFkxmTDMGFjDLBleGh3L8zlhuO 9vcq6rom3TonOONxyJ1TlG3dz2Tu3xZNtzTLgZu21y1r0dOW/HLntrgdi9ow hlHTsnRVbJ98DxjYs/K87Q1rJjWazCO7kHbIXUj9DS7dSMHVNSmhwrjHMc8D INk476V5jJDmnOPXZM38aeAd+DUp/39ccxmDEf3H7u30Rk6zDLGZkPYNq9CP Pzj39xsVe+KeupMjKsjONsG6dk1bajByHYPOMHxneP2Og3q+dR9ryGk19o0n onYPUfEfhVc1V+kcbJwmQ/nRwn3Hp6pP4TqvTO/2TfNJkvrrbt8+a9N92oy2 FeXUOI8486Wvor1zajqPDfpwnrn2jOzvo8hkOPrpVajlwnjqPfIry5c0TbKL 559fx8xqpsquRaFYV9I9fT6p7RrI/Gv/F3JFOFCQRJtf/Q== ====</lang>

Perl 6

<lang perl6>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,");

}</lang> And that's how I larned it!

Phix

Translation of: Ada

<lang Phix>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!")</lang>

PHP

<lang 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";

}</lang>

PicoLisp

Translation of: C

<lang PicoLisp>(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))</lang>

PowerShell

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

$leng=$arr.length $animals=@() for($i=0;$i -lt $leng;$i++){ $split=$arr[$i] -split "/" $animals+=$split[0] $comment=$split[1] write-host "I know an old lady who swallowed a" $animals[$i] if($comment){write-host "$comment"} if($i -eq $leng-1){break} for($j=$i;$j -ge 1;$j--){ write-host "She swallowed the" $animals[$j] "to catch the" $animals[$j-1] } write-host "I don't know why she swallowed the fly." write-host "Perhaps she'll die." write-host "" }</lang>

Python

<lang 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"))</lang>

<lang python>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</lang>

Racket

<lang racket>

  1. 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)))])))

</lang> Alternative solution: <lang racket>

  1. lang s-exp framework/private/decode

7VK7TsQwEOz9FcM1AcncZyCoQaLey/piCyuObJ+s/D3rXHj4lIIKgaCItJkZ7cyOfM0uTZ5m 7J6siQaFEmhE8AxPPCNbykiFvA/FMAhHP2v1AA5jl/EyhoJiZyRrLlW4xWSipSlVtvMe7MyV Ul/0SZNjE7XIhSjRDYOv+Mgon+a8zm5MIoes3qvHJkuuf8su5ICecm8X7LvuOLjIWt3Lfjqk U+SaYuVXditxxdu8b338rOvEUas7GvuVa44Tcuu2/qz7CHuu6PeWwGHQ6rmiBCtz24KwWy0I 3KZdqvwDbfWhXPhY+S59RLX5dkTapF66/2/3fYMNMZklVJfAhlgjHKW2k8B7tbtRrw== </lang>

REXX

<lang rexx>/*REXX pgm displays song lyrics for "I Know an Old Lady who Swallowed a Fly". */ sw=79 /*width of terminal screen, -1.*/ I_know= "I know an old lady who swallowed a" @ate = 'She swallowed the'; @2catch= "to catch the"  ; @.= 

 @.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($)
                                                   /* [↓]  display blank line*/
 do j=1  for #;    fauna=word($,j);                   say
 say center(I_know fauna',', sw);     if j\==1  then  say center(@.j, sw)
 if j==#  then leave                               /*Last verse?  We're done.*/
                      do k=j  to 2  by -1;                       km=k-1
                      say center(@ate word($,k)  @2catch  word($,km)',',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. */</lang>

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

<lang 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</lang>

Rust

<lang rust>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");
   }

}</lang>

Scala

<lang 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
 }

}</lang>

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!

Seed7

<lang 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;</lang>

Sidef

Translation of: Perl 6

<lang ruby>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},");

};</lang>

Tcl

Because the song is highly repetitive, it compresses wonderfully. <lang tcl>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=

"]]</lang>

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)). <lang txr>@(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") ("T" "cat") ("R" "bird")
  ("S " "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 T"
   "SW T CA R"
   "SW R CA S"
   "SW S 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!"
  "T: Imagine that! She swallowed a T!"
  "R: How absurd to swallow a R!"
  "S: 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)</lang>

UNIX Shell

Works with: Bash

<lang sh>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</lang>

Ursa

Translation of: C#

<lang ursa>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 endl console
       out comments 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</lang>

zkl

Translation of: Tcl

Uncompresses the base64 encoded gziped text of the song. Uses shared libraries zlib and msg hashing for the codecs. <lang zkl>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();</lang>

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!!
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