jeffreykegler

perl bench.pl /usr/share/iso-codes/json/iso_639-3.json
Using /usr/share/iso-codes/json/iso_639-3.json
Using Marpa::R2 8
            (warning: too few iterations for a reliable count)
            (warning: too few iterations for a reliable count)
            (warning: too few iterations for a reliable count)
             s/iter ESLIF JSON  SLIF JSON   JSON::PP   JSON::XS
ESLIF JSON     7.43         --       -10%       -71%      -100%
SLIF JSON      6.68        11%         --       -68%      -100%
JSON::PP       2.13       249%       214%         --       -99%

jeffreykegler

make basic
perl bench.pl test.json
Using test.json
Using Marpa::R2 8
              Rate  SLIF JSON   JSON::PP ESLIF JSON   JSON::XS
SLIF JSON    107/s         --       -71%       -76%      -100%
JSON::PP     366/s       241%         --       -18%       -99%
ESLIF JSON   449/s       318%        23%         --       -99%
JSON::XS   38642/s     35944%     10465%      8514%         --

jeffreykegler

The post An Overview Of The Marpa Parser was originally published at https://lukasatkinson.de/2015/marpa-overview/.

---

Parsing pervades all of computing. Whenever we are dealing with some data format or a programming language, something needs to parse that. But writing a good grammar for a given language, and picking a suitable parser is not always easy.

For example, let's look at some strings in an example language:

jeffreykegler

#!perl

# This calculator contains *TWO* DSL's.
# The first one is for the calculator itself.
# The calculator's grammar is written in OP2.
# OP2 is the second DSL, and its code is the
# second half of this file.

use 5.010;
use strict;

jeffreykegler

#!/usr/bin/perl
# Copyright 2013 Jeffrey Kegler
# This file is part of Marpa::R2.  Marpa::R2 is free software: you can
# redistribute it and/or modify it under the terms of the GNU Lesser
# General Public License as published by the Free Software Foundation,
# either version 3 of the License, or (at your option) any later version.
#
# Marpa::R2 is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

jeffreykegler

#!perl
use strict;
use warnings;
use 5.010;
use Data::Dumper;
use Marpa::R2;

sub My_Actions::dwim {
    shift;
    return $_[0] if scalar @_ == 1;

jeffreykegler

#!perl
use strict;
use warnings;
use 5.010;
use Data::Dumper;
use Marpa::R2;

sub My_Actions::dwim {
    shift;
    return $_[0] if scalar @_ == 1;

jeffreykegler

#!perl
use strict;
use warnings;
use 5.010;
use Data::Dumper;
use Marpa::R2;

sub My_Actions::dwim {
    shift;
    return $_[0] if scalar @_ == 1;

jeffreykegler

#!perl
use strict;
use warnings;
use 5.010;
use Data::Dumper;
use Marpa::R2;

# This grammar tries to be equivalent to a PEG or Regex with ordered choice:
# List: Item*
# Item: VAR = VAR // VAR = // VAR

jeffreykegler

#!/usr/bin/perl

use 5.010;
use strict;
use warnings;

use Data::Dumper;
use English qw( -no_match_vars );

use Test::More tests => 6;