Re^2: Perl Complains of Nested Quantifiers

Thanks. That clarifies things. Unfortunately, I am stuck using this ancient version due to various reasons.

Thanks everyone for all of your assistance in this matter.

Comment on Re^2: Perl Complains of Nested Quantifiers

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Re^3: Perl Complains of Nested Quantifiers by demerphq (Chancellor) on May 22, 2012 at 21:33 UTC
FWIW the "possessive modifier" is simply syntactic sugar for `(?>...)` so `(?>x+)` should produce exactly the same optree as `x++`. `$ perl -Mre=debug -e'/x++/' Compiling REx "x++" Final program: 1: SUSPEND (8) 3: PLUS (6) 4: EXACT <x> (0) 6: SUCCEED (0) 7: TAIL (8) 8: END (0) anchored "x" at 0 (checking anchored) minlen 1 Freeing REx: "x++" $ perl -Mre=debug -e'/(?>x+)/' Compiling REx "(?>x+)" Final program: 1: SUSPEND (8) 3: PLUS (6) 4: EXACT <x> (0) 6: SUCCEED (0) 7: TAIL (8) 8: END (0) anchored "x" at 0 (checking anchored) minlen 1 Freeing REx: "(?>x+)"` [download] so there is nothing stopping you using it in 5.8.8 --- $world=~s/war/peace/g	[reply] [d/l] [select]

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Re^3: Perl Complains of Nested Quantifiers
by demerphq (Chancellor) on May 22, 2012 at 21:33 UTC

FWIW the "possessive modifier" is simply syntactic sugar for (?>...) so (?>x+) should produce exactly the same optree as x++.

$ perl -Mre=debug -e'/x++/'
Compiling REx "x++"
Final program:
   1: SUSPEND (8)
   3:   PLUS (6)
   4:     EXACT <x> (0)
   6:   SUCCEED (0)
   7: TAIL (8)
   8: END (0)
anchored "x" at 0 (checking anchored) minlen 1 
Freeing REx: "x++"
$ perl -Mre=debug -e'/(?>x+)/'
Compiling REx "(?>x+)"
Final program:
   1: SUSPEND (8)
   3:   PLUS (6)
   4:     EXACT <x> (0)
   6:   SUCCEED (0)
   7: TAIL (8)
   8: END (0)
anchored "x" at 0 (checking anchored) minlen 1 
Freeing REx: "(?>x+)"
[download]

so there is nothing stopping you using it in 5.8.8

---
$world=~s/war/peace/g

[reply]
[d/l]
[select]