CHANGESTR.REX: Difference between revisions
(added a sample REXX code for the CHANGESTR subroutine. -- ~~~~) |
Walterpachl (talk | contribs) m (correct spelling(s)) |
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║ original string (haystack)────────┐ │ │ [default: ≈ one billian]║ |
║ original string (haystack)────────┐ │ │ [default: ≈ one billian]║ |
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║ old string to be changed───┐ │ │ │ ┌───begin at this occurance #.║ |
║ old string to be changed───┐ │ │ │ ┌───begin at this occurance #.║ |
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║ {O, H, and N can be null.} │ │ │ │ │ [default: 1st |
║ {O, H, and N can be null.} │ │ │ │ │ [default: 1st occurrence]║ |
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╚═╦════════════════════════════╗ │ │ │ │ │ ╔═══════════════════════╦═╝ |
╚═╦════════════════════════════╗ │ │ │ │ │ ╔═══════════════════════╦═╝ |
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╚════════════════════════════╝ ↓ ↓ ↓ ↓ ↓ ╚═══════════════════════╝*/ |
╚════════════════════════════╝ ↓ ↓ ↓ ↓ ↓ ╚═══════════════════════╝*/ |
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w=length(o) /*length of OLD string.*/ |
w=length(o) /*length of OLD string.*/ |
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if w==0 & t\=0 then return n || h /*changing a null char ? */ |
if w==0 & t\=0 then return n || h /*changing a null char ? */ |
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#=0 |
#=0 /*# of changed occurrences*/ |
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do j=1 until # >= t /*keep changing, T times.*/ |
do j=1 until # >= t /*keep changing, T times.*/ |
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parse var h y (o) _ +(w) h /*parse the string ... */ |
parse var h y (o) _ +(w) h /*parse the string ... */ |
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else do |
else do |
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$=$ || y || n /*build new STR from S. */ |
$=$ || y || n /*build new STR from S. */ |
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#=#+1 /*bump |
#=#+1 /*bump occurrence number.*/ |
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end |
end |
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end /*j*/ |
end /*j*/ |
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Revision as of 12:08, 2 August 2013
<lang rexx>/*╔══════════════════════════════╗ CHANGESTR ╔═════════════════════════╗ ╔═╩══════════════════════════════╝ function ╚═════════════════════════╩═╗ ║ new string to be used──────────┐ ┌─────limit of # changes (times)║ ║ original string (haystack)────────┐ │ │ [default: ≈ one billian]║ ║ old string to be changed───┐ │ │ │ ┌───begin at this occurance #.║ ║ {O, H, and N can be null.} │ │ │ │ │ [default: 1st occurrence]║ ╚═╦════════════════════════════╗ │ │ │ │ │ ╔═══════════════════════╦═╝
╚════════════════════════════╝ ↓ ↓ ↓ ↓ ↓ ╚═══════════════════════╝*/
changestr: procedure; parse arg o,h,n,t,b /* T and B are optional.*/ $= /*$: the returned string.*/ t=word(t 999999999 , 1) /*maybe use the default? */ b=word(b 1 , 1) /* " " " " */ w=length(o) /*length of OLD string.*/ if w==0 & t\=0 then return n || h /*changing a null char ? */
- =0 /*# of changed occurrences*/
do j=1 until # >= t /*keep changing, T times.*/
parse var h y (o) _ +(w) h /*parse the string ... */
if _== then return $ || y /*no more left, return. */
if j<b then $=$ || y || o /*didn't meet begin at ? */
else do
$=$ || y || n /*build new STR from S. */
#=#+1 /*bump occurrence number.*/
end
end /*j*/
/*Most REXX BIFs only ···*/
return $ || h /* support three options.*/</lang>