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#!/usr/bin/env perl
# Copyright 2015 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser
# General Public License along with Marpa::R2. If not, see
use 5.010;
use strict;
use Marpa::R2 2.097_002;
use Test::More tests => 3;
use Getopt::Long ();
my $verbose;
die if not Getopt::Long::GetOptions( verbose => \$verbose );
# This example tests the Ruby Slippers using the SLIF
my $grammar = << '=== GRAMMAR ===';
:default ::= action => [ name, value ]
lexeme default = action => [ name, value ] latm => 1 # to add token names to ast
script ::= E+ separator => semi action => [values]
E ::=
number action => main::number
|| E ('*') E action => main::multiply
|| E ('+') E action => main::add
:discard ~ whitespace
whitespace ~ [\s]+
number ~ [\d]+
semi ~ ';'
=== GRAMMAR ===
my $g = Marpa::R2::Scanless::G->new( { source => \($grammar) } );
my @tests = (
[ '1+2+3*4', '15' ],
[ '1+2 3+4', '3,7' ],
[ '0+42 21*2 3*7+21 3*7*2', '42,42,42,42' ],
);
for my $test (@tests) {
my ( $string, $expected_result ) = @{$test};
my $actual_result = test( $g, $string );
say "Input: $string";
Test::More::is( $actual_result, $expected_result,
qq{Result of "$string"} );
} ## end for my $test (@tests)
sub test {
my ( $g, $string ) = @_;
my @found = ();
diag("Input: $string") if $verbose;
my $original_length = length $string;
my $suffixed_string = $string . ';';
my $target_start = 0;
# state $recce_debug_args = { trace_terminals => 1, trace_values => 1 };
state $recce_debug_args = {};
# Marpa::R2::Display
# name: SLIF rejection recognizer setting synopsis
my $recce = Marpa::R2::Scanless::R->new(
{ grammar => $g,
rejection => 'event',
},
$recce_debug_args
);
my $pos = $recce->read( \$suffixed_string, 0, $original_length );
READ_LOOP: while (1) {
my $rejection = 0;
my $pos = $recce->pos();
EVENT:
for my $event ( @{ $recce->events() } ) {
my ($name) = @{$event};
if ( $name eq q('rejected) ) {
$rejection = 1;
diag("You fool! you forget the semi-colon at location $pos!")
if $verbose;
next EVENT;
} ## end if ( $name eq q('rejected) )
die join q{ }, "Spurious event at position $pos: '$name'";
} ## end EVENT: for my $event ( @{ $recce->events() } )
last READ_LOOP if not $rejection;
$recce->resume( $original_length, 1 );
diag("I fixed it for you. Now you owe me.") if $verbose;
$recce->resume( $pos, $original_length - $pos );
} ## end READ_LOOP: while (1)
# Marpa::R2::Display::End
my $ref_value = $recce->value();
return 'No parse' if not $ref_value;
if ( ref $ref_value ne 'REF' ) {
my $ref_type = ref $ref_value;
my $ref_description = $ref_type ? "ref to $ref_type" : 'not a ref';
return "Got $ref_description -- want REF to REF to ARRAY";
}
return join q{,}, @{ ${$ref_value} };
} ## end sub test
sub number {
my ( undef, $v1 ) = @_;
return $v1->[1];
}
sub add {
my ( $undef, $v1, $v2 ) = @_;
return $v1 + $v2;
}
sub multiply {
my ( $undef, $v1, $v2 ) = @_;
return $v1 * $v2;
}
# vim: expandtab shiftwidth=4: