in reply to Using a regex capture as part of a varible

Never used it but looking at the source I'm not sure that it'll do what you want. Your second argument is getting passed in as $replace into this bit of code: 

  else {
    @content = split( /\n/, cat($file) );
    for (@content) {
      s/$search/$replace/;
    }
  }

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You've tried to quote things correctly, but for that to work there'd need to be an /ee modifier on the substitution to get it evaluate the contents of $replace and then replace with what that expanded text contains. Unless there's some new dark magic I'm not aware of for expansions that lets you turn on /ee at a distance I don't think it's capable of what you're trying to do.

Edit: Aah you've got the multiline option set; the substitution would be the similar s///mgs a few lines earlier but the problem remains the same (it'd need to be s///mgsee to expand $replace and then evaluate the expanded value).

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Re^2: Using a regex capture as part of a varible
by nysus (Parson) on May 07, 2020 at 14:49 UTC

    OK, good to know. My brain seems to have lost all knowledge of the 'e' modifier. Tried to get it to work with this simple example: 

    my $new = 'blah';
my $string = 'asdfjkjl';
my $find = '(asd)';
my $replace = '$1' . $new;

replace ($string, $find, $replace);

sub replace {
  my $string = shift;
  my $left = shift;
  my $replace = shift;
  $string =~ s/$left/$replace/e;
  print $string;
}

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    Still prints $1 in the output though. Adding 'ee' throws an error: "Bareword found where operator expected at (eval 1) line 1, near "$1blah"

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[d/l]

      You need to set up your replacement string correctly. Once that's done it runs fine with the /ee modifier:

      use strict;
use warnings;

use Test::More tests => 1;                      

my $new     = 'blah';
my $string  = 'asdfjkjl';
my $find    = '(asd)';
my $replace = qq#\${1} . '$new'#;

my $result = replace ($string, $find, $replace);

is $result, 'asdblahfjkjl';

sub replace {
    my $string  = shift;
    my $left    = shift;
    my $replace = shift;
    $string =~ s/$left/$replace/ee;
    return $string;
}

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