Can you give a bit of working code (edit: I mean, code that give that error) that demonstrates the problem (using XML::Validator::Schema if you have to)?
As noted here, there are limits, but maybe you can work around it.
Also, these paragraphs in http://search.cpan.org/src/NWCLARK/perl-5.8.4/hints/machten.sh
claim that you can compile perl with higher limits on regex repeats, irrespective of the architecture defaults:
# Set reg_infty -- the maximum allowable number of repeats in regular
# expressions such as /a{1,$max_repeats}/, and the maximum number of
# times /a*/ will match. Setting this too high without having a stack
# large enough to accommodate deep recursion in the regular expression
# engine allows perl to crash your Mac due to stack overrun if it
# encounters a pathological regular expression. The default is a
# compromise between capability and required stack size (see below).
# You may override the default value from the Configure command-line
# like this:
#
# Configure -Dreg_infty=16368 ...
reg_infty=${reg_infty:-2047}
# If you want to have many perl processes active simultaneously --
# processing CGI forms -- for example, you should opt for a small stac
+k.
# For safety, you should set reg_infty no larger than the correspondin
+g
# value given in this table:
#
# Stack size reg_infty value supported
# ---------- -------------------------
# 128k 2**8-1 (256)
# 256k 2**9-1 (511)
# 512k 2**10-1 (1023)
# 1M 2**11-1 (2047)
# ...
# 16M 2**15-1 (32767) (perl's default value)
# This script selects a safe stack size based on the value of reg_inft
+y
# specified above. However, you may choose to take a risk and set
# stack size lower: pathological regular expressions are rare in real-
+world
# programs. But be aware that, if perl does encounter one, it WILL
# crash your system. Do not set stack size lower than 96k unless
# you want perl's installation tests ( make test ) to crash your syste
+m.
#
# You may override the default value from the Configure command-line
# by specifying the required size in kilobytes like this:
#
# Configure -Dstack_size=96
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[d/l] |
Can you give a bit of working code (edit: I mean, code that give that error) that demonstrates the problem (using XML::Validator::Schema if you have to)?
That would be hard, and probably useless. I'm pretty well convinced that there are hard limits on the regex repetition operators which I can't avoid. Even if you can recompile Perl to make them bigger, that doesn't mean they'll ever go away. I guess I'll just document the limitation in XML::Validator::Schema and leave it at that.
The only thing I can't figure out is why my attempts to verify that those limits exist failed.
-sam
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Your attempts used too-simple constructs so they didn't have the limit.
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