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Postings from September 2006
From S05:
If a subrule appears two (or more) times in any branch of a lexical
scope (i.e. twice within the same subpattern and alternation), or if the
subrule is quantified anywhere within a given scope, then its
corresponding hash entry is always assigned an array of
C<Match> objects rather than a single C<Match> object.
However, fglock and I both find the "quantified" clause very surprising.
Intuitively:
/<foo> bar bar <foo>/
should set $<foo> to an Array with two Match elements. However:
/<foo>+/
should set $<foo> to a single Match, with multiple positional Match
elements, each
one representing one match in the quantified match. Moreover:
/<foo> bar bar <foo>+/
should set $<foo> to an Array with two Match elements, the first being a
simple match, and the second has multiple positional submatches.
The thinking behind the separate treatment is that in a contiguous
quantified
match, it does make sense to ask the .from and .to for the entire
range, which
is very hard to do if it's an Array (which can have 0 elements,
rendering $<foo>[-1].to
dangerous). Also stringification for $<foo> on a /<foo>+/ match
should perhaps
not be space-separated, i.e. it should follow Match semantics not
Array semantics.
To recap: Is it possible to amend the quantified clause to have it
produce Match
objects, and reserve Array only for noncontiguous same-named subrules?
Thanks,
Audrey
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