|Syntactic Confectionery Delight|
Perl 5.17 change to use re 'eval' breaks Acme::EyeDropsby eyepopslikeamosquito (Chancellor)
|on Apr 25, 2013 at 03:31 UTC||Need Help??|
eyepopslikeamosquito has asked for the
wisdom of the Perl Monks concerning the following question:
Though running this program, v1.pl:
works fine with perl 5.16, running it with perl 5.17.10 produces an error:
Note that the Acme::EyeDrops-generated string being eval'ed above is a constant expression, as can be seen by running:
Note further that running the deparsed program above works fine in perl 5.17 without requiring a leading use re 'eval'.
Though v1.pl can be made to work with perl 5.17.10 by adding a leading:
this destroys the artistic effect of having no alphanumeric characters at all. :) Moreover, I wonder why this is necessary, given the string being eval'ed is a constant expression and given that the deparsed program does not require it.
This change in use re 'eval' behavior was presumably introduced by Dave Mitchell's "re_eval jumbo fix" (see also ticket #113682). Given my test program above does not use tieing or overloading and no variables are interpolated in the (constant) expression, I wonder if this is a Perl 5.17 bug -- or am I missing something?
Assuming that use re 'eval' is really required for Perl v5.17.1+, I will need to fix the Acme::EyeDrops test suite to pass with the upcoming perl 5.18. Though adding a leading:
both seem to work fine, which is preferred?