You know why single quotes don't work; variables don't get interpolated in single-quoted strings.

Double quotes don't work because the value of the string which interpolates $1 gets evaluated at the point of assignment, which occurs before the regular expression match.

You need to delay the evaluation of $1 until the point at which it contains a value you want to interpolate into a string. One way to do that is to define $outputString within the if block. Another approach is to use an anonymous function.

use 5.010;

my $make_output_string = sub { "this is a $_[0]" };

...

if ($sample_data =~ m/$search_string/)
{
    say $make_output_string->($1);
}

[download]

(You don't have to use 5.10 to make this work, but I really like say.)

In reply to Re: Uninitialized scalar inside a scalar? by chromatic
in thread Uninitialized scalar inside a scalar? by n00bsauce

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