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Postings from August 2010
On Tue, 03 Aug 2010, Eric Brine wrote: > On Tue, Aug 3, 2010 at 8:53 PM, Jan Dubois <jand@activestate.com> wrote: > > On Tue, 03 Aug 2010, karl williamson wrote: > > > > > > The problem is what those modifiers should be. Perl currently allows a > > > keyword to come right after a regex, like '/abc/lt 1' > > > > Is there are comprehensive list of all potential conflicts? > > http://www.nntp.perl.org/group/perl.perl5.porters/2010/05/msg160173.html Ah yes, thanks! | Any of the following immediately following the delimiter are currently | valid, but will become a syntax error (e.g. /foo/le+1) or different valid | code (e.g. /foo/lt+1): | | - unless & until from /u | - le & lt from /l | - [none] from /t I don't understand what [none] means here, and how it becomes a syntax error. | We're precluded from using these: | | - /a (and) | - /f (for, foreach) | - /n (ne) | - /w (when, while) So this means Karl's potential implementation of (6) essentially means that when a regexp is immediately followed by one of the 10 keywords above, then the letters won't be interpreted as regexp modifiers, but in every other case the letters must either be valid modifiers or will generate a syntax error. And we can even use /a, /f, /n, and /w with the restriction that e.g. /ne has to be re-ordered as /en for now. If I understand this correctly, then I certainly prefer (6) over the other solutions, given that it preserves full backward compatibility (for 5.14), but also lets us choose the right mnemonic characters for the new modifiers, and avoid the abomination of double-character modifiers. The temporary restriction on the 10 keywords does seem to forbid mostly non-sensical or invalid modifier combinations anyways (except for /le and potentially /ne), so it doesn't even make a practical difference anyways. Cheers, -JanThread Previous | Thread Next