I don't see how a module could reduce the code substantially since only the dispatch loop is reusable.

You can sweep a lot of the nitty-gritty details under the carpet by using a module I wrote :)

use Regexp::Assemble;

my $ra = Regexp::Assemble->new->track(1);

my %dispatch = (
  '^(?!START:|END:)([^*: ][^:]+):(.+)\n' => sub {
      my $r = shift;
      process_record($r);  # first time will be empty record...
      %$r = ();            # clear the record
      $r->{name} = $ra->mvar(1);
      $r->{desc} = $ra->mvar(2);
  },
  '^START:\s*(.+)\n' => sub { $_[0]->{starttime} = $ra->mvar(1) },
  '^END:\s*(.+)\n'   => sub { $_[0]->{endtime}   = $ra->mvar(1) },
  '^(?:\* |  )([^:]+):(\d+):(.+)\n' => sub {
    my @captures = @{$ra->mvar()};
    push @{$_[0]->{items}}, [@captures[1..$#captures]],
  },
);

# add all the regular expressions to the R::A object
$ra->add( keys %dispatch );

my $r = {}; # 'record'
LINE: while (my $line = <DATA>) {
  # if we have a match, take the initial regular expression that match
+ed
  # and use it as a key into our dispatch table and call its value.
  $ra->match($line) and &$dispatch{$ra->matched}->($r);
}
process_record($r);

[download]

I would be inclined to chomp $line, and remove the \n's from your expressions, but that's just personal taste.

The trick is that when you enable tracking on a Regexp::Assemble object, when a match is made, it is able to recover the initial pattern that triggered the match. Therefore, you can use it as a key into a dispatch table, and things will Just Work.

You have to use the mvar method to recover the values of $1, $2, $3... etc, because they are lost in scope by the time control flow gets back to your code. The first element returned by mvar() without a specfific parameter is another way of recovering the original pattern; it's a byproduct of walking down the @- and @+ arrays at the time of the match.

*ponders*

which leads me to conclude that there should be a method call that returns only the $1..$n array of captures...

- another intruder with the mooring in the heart of the Perl

In reply to Re: Munging with a regex dispatch table (with Regexp::Assemble) by grinder
in thread Munging with a regex dispatch table by Solo

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