w.r.t the warning redirect, I've been preferring a local clobber of the __WARN__ handler recently. It's less intimidating to the unwashed, and expires naturally. 

use strict;
use warnings;

my $log = parse_regex( q#(\\.|["']|x)# );
print $log;


sub parse_regex {
  my ($regex) = @_;

  # Catch and stash warnings 
  my $parselog = '';
  local $SIG{__WARN__} = sub {
    $parselog .= $_ for @_;
  };

  # --- compile regex
  eval q{
   use re 'debug';
   qr/$regex/;
  };

  return $parselog;
}

[download]

Best of luck; strikes me as an interesting challenge. Is use re 'debug'; output stable enough for automated parsing?

Update: Huh, the debug actually bypasses the warning handler and prints directly to STDERR. Now starting penance.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: Parsing and translating Perl Regexes by kennethk
in thread Parsing and translating Perl Regexes by LanX

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