Several problems here:
  1. Array indexing starts at 0, not 1.
  2. In character classes (inside square brackets in a regex) you do not have to backslash brackets. ^ on the non-first position in a character class stands for itself.
  3. There are no capturing parentheses in the code, so $1 would be empty even if it worked.
  4. You have to evaluate the right hand side to turn the string $1 into the variable. 

#!/usr/bin/perl
use warnings;
use strict;

sub replace {
    s/$_[0]/$_[1]/eeg;
}


$_ = 'a { b } c ( d ) e';

my $nobrackets = qr/[^{}]+/;
replace(qr/\{($nobrackets)\}/, '$1');

print "$_\n";

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In reply to Re: Regex - Is there any way to control when the contents of a variable are interpolated? (Using "$1" and '$1' in regex replacements) by choroba
in thread Regex - Is there any way to control when the contents of a variable are interpolated? (Using "$1" and '$1' in regex replacements) by JDoolin

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