Re^2: Are beheaded strings known to be slow?

[NERDVANA]

That's unfortunate... I have code that is using regexes on File::Map buffers under the assumption it was an efficient way to scan through a file. Maybe there's room for one more optimization that checks the length of what needs copied vs. the length of the source scalar? In the example, each iteration only needs to put a single character in $&.

[ikegami]

You're forgetting about $` and $'. Between $`, $' and $&, the entire string is covered.

[NERDVANA]

Also unfortunate...

Maybe it would be neat if there was a new feature that turned those off for any match in the scope where it was disabled... to maybe be added to some future "use v5.46".

Or, maybe Regexp refs should have methods, so the regex engine can be used without affecting *any* global variables.

my $match= qr/(\d+)/->match($subject);
say $match->captures->[0] if $match;