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Postings from August 2010
Typo corrected below karl williamson wrote: > demerphq wrote: >> On 4 August 2010 15:38, karl williamson <public@khwilliamson.com> wrote: >>> Aristotle Pagaltzis wrote: >>>> * Ben Morrow <ben@morrow.me.uk> [2010-08-01 22:35]: >>>>> My alternative suggestion was to introduce a new grouping >>>>> construct, which I tentatively called (?~sixm:) (I don't much >>>>> like that, but there aren't many alternatives at this point), >>>>> which *does* do what you expect; and use that for >>>>> stringification instead. That way we change the stringification >>>>> once, now, and then never again. >>>> I’m unsure about how good an idea that is. >>>> >>>> Presumably the defaults can change in a future version of Perl, >>>> in which case a stringified pattern that uses this syntax will >>>> mean different things on different Perl versions. In some cases >>>> this will even magically do what you want, but it could equally >>>> be a pitfall. >>> FWIW, I have given this some thought, and came to the conclusion that >>> Perl >>> is almost certainly never going to change the defaults, because of the >>> backward compatibility issues. >> >> Except that its been discussed many times that being able to specify >> the default flags in a lexically scoped manner would be a useful >> feature. So while it might be true that /perl/ will not change the >> default flags, it is quite conceivable that perl will provide the user >> a way to do so. > > Certainly, but it's not relevant here, as this construct would not be > affected by those. (I now think a period is better than an underscore, > so will use that in the examples.) (?.:foo) would mean this cluster > does not inherit the surrounding flags, but uses the /perl/ default > ones. (?.x:foo) means this cluster does not inherit the surrounding > flags, but uses the /perl/ default ones, but also the x modifier is > selected, whether or not it is a /perl/ default. > > Whatever the user has chosen to be the default, it will be shown in the > stringification iff it differs from the /perl/ default. >Thread Previous | Thread Next