> Any code you call -- library routines etc. -- after you run the regex, but before you want to use its results, might also use the regex engine and overwrite those temporary global variables

Invoking the regex engine in a different scope doesn't matter, the variables are properly dynamically scoped: 

#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

sub call_me {
    "xyz" =~ /(..)/;
    say $1;
}

"abc" =~ /(.)/;
call_me();
say $1;  # Still "a".

[download]

Which doesn't mean I recommend using them.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

[download]

In reply to Re^4: non-capture mode sometimes erases previous capture by choroba
in thread non-capture mode sometimes erases previous capture by raygun

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