Re: ref() and Regexp

You shouldn't ever have to think about what string ref() returns. By comparing it to a prototype of the same thing, you insulate yourself from version changes and thinkos (like me forgetting if it's REGEX, REGEXP, Regex, or Regexp):

if( ref $regex eq ref qr// ) { ... }
[download]

Or, hide that in a subroutine is_regex() or something similar.

--
brian d foy <brian@stonehenge.com>
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Re^2: ref() and Regexp by ikegami (Patriarch) on Jan 31, 2008 at 20:02 UTC
Or, hide that in a subroutine is_regex() or something similar. Like this? `BEGIN { if (!defined(&re::is_regexp)) { package re; my $re_class = ref qr//; is_regexp = sub($) { local __ANON__ = 'is_regexp'; return UNIVERSAL::isa($_[0], $re_class); }; } }` [download] Using your philosophy to avoid magical constants, it checks if `re::is_regexp` is defined rather than checking `$]` for 5.10. `BEGIN` and the prototype duplicates the behaviour of 5.10's `re::is_regexp`. It uses `isa` instead of `ref` so regexes can be made detectable even if there's a need to rebless the regex (by adding `Regex` to that class's `@ISA`). It's not an invitation for non-regexes to pretend to be regexes.	[reply] [d/l] [select]
Re^3: ref() and Regexp by HeatSeekerCannibal (Beadle) on Feb 01, 2008 at 01:26 UTC
Whoa! So I could use this function for a problem like this? XML & Schema VS Config::IniFiles ....crossing fingers... Heatseeker Cannibal	[reply]
Re^2: ref() and Regexp by Anonymous Monk on Sep 13, 2009 at 10:37 UTC
Wouldn't qr/FOO/ be cheaper? (an empty regex is special)	[reply]
Re^3: ref() and Regexp by JadeNB (Chaplain) on Dec 16, 2009 at 00:09 UTC
an empty regex is special In a match (see `m//`), but not for `qr//`: `$ perl -e 'print qr//;' (?-xism:)` [download]	[reply] [d/l] [select]