1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
#!perl
# Copyright 2014 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
# http://www.gnu.org/licenses/.
# Tests of ambiguity detection in the target grammar
# (as opposed to the SLIF DSL itself).
use 5.010;
use strict;
use warnings;
use Test::More tests => 4;
use English qw( -no_match_vars );
use lib 'inc';
use Marpa::R2::Test;
use Marpa::R2;
use Data::Dumper;
our $DEBUG = 0;
my $source = \(<<'END_OF_SOURCE');
:default ::= action => ::array
pair ::= duple | item item
duple ::= item item
item ::= Hesperus | Phosphorus
Hesperus ::= 'a'
Phosphorus ::= 'a'
END_OF_SOURCE
my $input = 'aa';
my $expected_value = 'Application grammar is ambiguous';
my $expected_result = <<'END_OF_MESSAGE';
Ambiguous symch at Glade=2, Symbol=<pair>:
The ambiguity is from line 1, column 1 to line 1, column 2
Text is: aa
There are 2 symches
Symch 0 is a rule: pair ::= duple
Symch 1 is a rule: pair ::= item item
END_OF_MESSAGE
my $test_name = 'Symch ambiguity';
my $grammar = Marpa::R2::Scanless::G->new( { source => $source } );
my $recce = Marpa::R2::Scanless::R->new( { grammar => $grammar } );
my $is_ambiguous_parse = 1;
my ( $actual_value, $actual_result );
PROCESSING: {
if ( not defined eval { $recce->read( \$input ); 1 } ) {
say $EVAL_ERROR if $DEBUG;
my $abbreviated_error = $EVAL_ERROR;
chomp $abbreviated_error;
$abbreviated_error =~ s/\n.*//xms;
$actual_value = 'No parse';
$actual_result = $abbreviated_error;
$is_ambiguous_parse = 0;
last PROCESSING;
} ## end if ( not defined eval { $recce->read( \$input ); 1 })
# Marpa::R2::Display
# name: ASF ambiguity reporting
if ( $recce->ambiguity_metric() > 1 ) {
my $asf = Marpa::R2::ASF->new( { slr => $recce } );
die 'No ASF' if not defined $asf;
my $ambiguities = Marpa::R2::Internal::ASF::ambiguities($asf);
# Only report the first two
my @ambiguities = grep {defined} @{$ambiguities}[ 0 .. 1 ];
$actual_value = 'Application grammar is ambiguous';
$actual_result =
Marpa::R2::Internal::ASF::ambiguities_show( $asf, \@ambiguities );
last PROCESSING;
} ## end if ( $recce->ambiguity_metric() > 1 )
# Marpa::R2::Display::End
$is_ambiguous_parse = 0;
my $value_ref = $recce->value();
if ( not defined $value_ref ) {
$actual_value = 'No parse';
$actual_result = 'Input read to end but no parse';
last PROCESSING;
}
$actual_value = ${$value_ref};
$actual_result = 'Parse OK';
last PROCESSING;
} ## end PROCESSING:
Test::More::is(
Data::Dumper::Dumper( \$actual_value ),
Data::Dumper::Dumper( \$expected_value ),
qq{Value of $test_name}
);
Test::More::is( $actual_result, $expected_result, qq{Result of $test_name} );
if ( !$is_ambiguous_parse ) {
Test::More::fail(qq{glade_span() start});
Test::More::fail(qq{glade_span() length});
}
else {
$recce->series_restart();
my $asf = Marpa::R2::ASF->new( { slr => $recce } );
my $glade_id = $asf->peak;
# Marpa::R2::Display
# name: glade_span() example
my ( $glade_start, $glade_length ) = $asf->glade_span($glade_id);
# Marpa::R2::Display::End
Test::More::is( $glade_start, 0, qq{glade_span() start} );
Test::More::is( $glade_length, 2, qq{glade_span() length} );
} ## end else [ if ( !$is_ambiguous_parse ) ]
# vim: expandtab shiftwidth=4:
|
