Re^2: is perl's regular expression engine reentrant ? (works)

So I can do whatever I want on the "right side" with no undefined behaviour.

Great news!

I suppose you are saying that reentrancy is only an issue with ?{code} and ??{code} constructs.

I knew these were problematic (and experimental features) but thought that making substitutions using the re engine on the evaluated code could also be a problem.

Any idea where I can find documentation that mentions this explicitly

Thank you.

Comment on Re^2: is perl's regular expression engine reentrant ? (works)

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Re^3: is perl's regular expression engine reentrant ? (works) by betterworld (Curate) on Apr 27, 2007 at 03:22 UTC
I suppose you are saying that reentrancy is only an issue with ?{code} and ??{code} constructs. This is in fact an issue. The following one-liner will segfault (with perl 5.8.8): `perl -we '"_" =~ m{(??{"_" =~ /./})}'` [download]	[reply] [d/l]
Re^4: is perl's regular expression engine reentrant ? (works) by grinder (Bishop) on Apr 27, 2007 at 09:58 UTC
With the extensive rewrite of the regular expression engine, by dave_the_m and demerphq, that particular expression works just fine in the development version (what will become 5.10). `% perl5.9.5 -wle 'print +("_" =~ m{(??{"_" =~ /./})}) ? 1 : 0' 0 % perl5.9.5 -wle 'print +("_" =~ m{(??{"_" !~ /./})}) ? 1 : 0' 1` [download] There exist, however, more exotic code constructs that will trip up reentrancy bugs. • another intruder with the mooring in the heart of the Perl	[reply] [d/l]
Re^4: is perl's regular expression engine reentrant ? (works) by plank (Novice) on Apr 27, 2007 at 08:13 UTC
Again thank you for clarifying this with an example. You have been most helpful. If I find any extra info regarding this I will try to append it top the question for future reference.	[reply]