Dear Monks,

I'm trying to capture and remove certain substrings from a string. In this example I want to capture and remove words starting with 'foo', preserving the residual string.

#!/usr/bin/env perl
use v5.36;
my $x = "xyzzy foo1 foo2";
my @captured;
while ($x =~ s{ \s* (foo\w) \s* }{}msxg) {
    push @captured, $1;
}
say "Captured: '$_'" for @captured;
say "Left with '$x'";
[download]

This gives:

Captured: 'foo2'
Left with 'xyzzy'
[download]

Removing the 'g' option gives me what I want:

Captured: 'foo1'
Captured: 'foo2'
Left with 'xyzzy'
[download]

But I'm not clear why the regex 'g' option in a while-loop behaves differently for matching than for substitution.

Also, I'm wondering if there's a better way to capture and remove a repeated pattern from a string like the above.

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