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=head1 TITLE
Additions to regexs
=head1 VERSION
Maintainer: Richard Proctor <[EMAIL PROTECTED]>
Date: 27 Aug 2000
Mailing List: [EMAIL PROTECTED]
Version: 1
Number: 166
=head1 ABSTRACT
This is a set of minor enhancements to regexs that I thought up on a long
plane ride. All these can be done now, I would just like to make them
easier.
=head1 DESCRIPTION
These are a set of minor enhancements to regexes, they are largely independant.
=head2 Alternative Lists from arrays
(?@foo) is sort of equivalent to (??{join('|',@foo)}), ie it expands into a
list of alternatives. One could possible use just @foo, for this.
If @foo contained special characters you might want to \Quote each item.
(?Q@foo) is sort of equivalent to (??{join('|', map quotemeta, @foo)})
=head2 Matching Not a pattern
(?^pattern) matches anything that does not match the pattern. On its own, one
can use !~ etc to negatively match patterns, but to match a pattern that
has foo(anything but not baz)bar is currently difficult. With this syntax
it would simply be /foo(?^baz)bar/.
=head2 A disambiguator
(?) is a null element in a pattern, that can be used to split elements that
might otherwise be confused, it has no effect otherwise, it matches nothing.
If you have a variable $foo, then matching $foobar would look for the
variable $foobar, when you actually meant to look for $foo then "bar". This
allows the user to simply write $foo(?)bar. (Yes I know this can be written
other ways but this is a simple example).
=head1 IMPLENTATION
No Idea
=head1 REFERENCES
None yet
