#!/usr/bin/env perl use warnings; use strict; use Data::Dump; use Marpa::R2; my $rules = <<'END_OF_GRAMMAR'; lexeme default = latm => 1 :default ::= action => ::first entry ::= op hostaddr4 action => dump_entry op ::= 'add' action => add_op | 'remove' action => add_op hostaddr4 ::= hostname | ipv4 hostname ::= DOMAIN EXT action => add_hostname | DOMAIN DOMAIN EXT action => add_hostname | DOMAIN DOMAIN DOMAIN EXT action => add_hostname DOMAIN ::= NAME '.' NAME ~ [\d\w]+ EXT ~ 'org' | 'net' ipv4 ::= NUMBER '.' NUMBER '.' NUMBER '.' NUMBER action => add_ip NUMBER ~ [\d]+ :discard ~ SP SP ~ [\s]+ END_OF_GRAMMAR my $input = <<'END_OF_INPUT'; add example.org add www.perl.org add 42.perl.net add 192.0.2.1 remove 192.0.2.2 END_OF_INPUT my $grammar = Marpa::R2::Scanless::G->new({source => \$rules}); for (split /^/m, $input) { chomp; if (length $_) { print "\nPARSING: $_\n"; my $recce = Marpa::R2::Scanless::R->new({ grammar => $grammar, }); my $value_ref = $grammar->parse( \$_, 'main'); } } sub dump_entry{ print "dump_entry received: "; dd shift @_; } sub add_op{ my $self = shift @_; print "add_op received: "; dd @_; $$self{operator} = join '',@_; return $self; } sub add_ip{ my $self = shift @_; print "add_ip received: "; dd @_; $$self{type} = 'IP'; $$self{value} = join '',@_; return $self; } sub add_hostname{ my $self = shift @_; print "add_hostname received: "; dd @_; $$self{type} = 'hostname'; $$self{value} = join '.',@_; return $self; } __DATA__ PARSING: add example.org add_op received: "add" add_hostname received: ("example", "org") dump_entry received: { operator => "add", type => "hostname", value => "example.org" } PARSING: add www.perl.org add_op received: "add" add_hostname received: ("www", "perl", "org") dump_entry received: { operator => "add", type => "hostname", value => "www.perl.org" } PARSING: add 42.perl.net add_op received: "add" add_hostname received: (42, "perl", "net") dump_entry received: { operator => "add", type => "hostname", value => "42.perl.net" } PARSING: add 192.0.2.1 add_op received: "add" add_ip received: (192, ".", 0, ".", 2, ".", 1) dump_entry received: { operator => "add", type => "IP", value => "192.0.2.1" } PARSING: remove 192.0.2.2 add_op received: "remove" add_ip received: (192, ".", 0, ".", 2, ".", 2) dump_entry received: { operator => "remove", type => "IP", value => "192.0.2.2" }