This runs about 20% faster for me, YMMV:

use strict;
use warnings;
use Benchmark;
my $match_list = 'a/ere,c/ere'; # verification pattern
my $markup = 'TY:X{a} X{c}'; # output markup
my $attrs = 'TY a=errt c=rrrdd'; # info to check
my $tag = 'TY'; # tag name

sub first_draft {
    my %xlist = map{ split('/', $_, 2) } # make list
    grep{ m'/' } split(',', $match_list);

    $attrs =~ s/\A$tag //; # clean up
    for (split (' ', $attrs)) {
     my ($name, $value) = split('=');
     # only one attribute of the same name is allowed.
     if (defined $xlist{$name}) {
      $xlist{$name} = undef; # this exists now
      $markup =~ s/X{$name}/$value/g;
     }
      else { # fails get nothing and end.
       $markup = '';
       last;
       }
     }
     # not in Benchmark
#     $markup
#     ? print $markup
#     : print 'nope';
}
     timethese($ARGV[0] || -1, {
    1 ?  (
        'first_draft'  => \&first_draft,
    ) : (),
});

[download]

I would expect there to be a more efficient way to set up %xlist but it hasn't occurred to me yet precisely how.

In reply to Re: Speeding up a Perl code. Can it be faster? by hippo
in thread Speeding up a Perl code. Can it be faster? by $h4X4_|=73}{

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