Re: Perl Complains of Nested Quantifiers

[ikegami]

You must be using a version of Perl before this feature was added (5.10 IIRC).

If so, you're using an ancient version of Perl. 5.8, 5.10 and now 5.12 have all been end-of-lifed. 5.14 is still supported, and 5.16.0 is the latest stable version.

[sunmaz]

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.

[demerphq]

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+)"

so there is nothing stopping you using it in 5.8.8