...where the parentheses are numbered by the position of the left parentheses, so "abc" =~ /((a)b(c))/ will set $1 to "abc", $2 to "a", and $3 to "c".

If you use a regex that has parentheses in list context, the substrings are returned in a list, and can be used directly: 

my ($abc, $a, $c) = "abc" =~ /((a)b(c))/

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see perlop for more information about m// and s/// and what they return and how flags like //g affect them.

In reply to Re: Re: Extract substring from string with no whitespace using regexp? by ysth
in thread Extract substring from string with no whitespace using regexp? by Elijah

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