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#!/usr/bin/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/.
# Synopsis for Scannerless interface
use 5.010;
use strict;
use warnings;
use Test::More tests => 4;
use English qw( -no_match_vars );
use Scalar::Util qw(blessed);
use lib 'inc';
use Marpa::R2::Test;
## no critic (ErrorHandling::RequireCarping);
use Marpa::R2;
my $slg = Marpa::R2::Scanless::G->new(
{ bless_package => 'My_Nodes',
source => \(<<'END_OF_SOURCE'),
:default ::= action => ::array bless => ::lhs
:start ::= Script
Script ::= Expression+ separator => comma bless => script
comma ~ [,]
Expression ::=
Number bless => primary
| ('(') Expression (')') assoc => group bless => parens
|| Expression ('**') Expression assoc => right bless => power
|| Expression ('*') Expression bless => multiply
| Expression ('/') Expression bless => divide
|| Expression ('+') Expression bless => add
| Expression ('-') Expression bless => subtract
Number ~ [\d]+
:discard ~ whitespace
whitespace ~ [\s]+
# allow comments
:discard ~ <hash comment>
<hash comment> ~ <terminated hash comment> | <unterminated
final hash comment>
<terminated hash comment> ~ '#' <hash comment body> <vertical space char>
<unterminated final hash comment> ~ '#' <hash comment body>
<hash comment body> ~ <hash comment char>*
<vertical space char> ~ [\x{A}\x{B}\x{C}\x{D}\x{2028}\x{2029}]
<hash comment char> ~ [^\x{A}\x{B}\x{C}\x{D}\x{2028}\x{2029}]
END_OF_SOURCE
}
);
# Marpa::R2::Display
# name: SLG show_rules() synopsis
my $show_rules_output = $slg->show_rules();
# Marpa::R2::Display::End
$show_rules_output .= $slg->show_rules(1, 'L0');
Marpa::R2::Test::is( $show_rules_output,
<<'END_OF_SHOW_RULES_OUTPUT', 'Scanless show_rules()' );
G1 R0 Script ::= Expression +
G1 R1 Expression ::= Expression
G1 R2 Expression ::= Expression
G1 R3 Expression ::= Expression
G1 R4 Expression ::= Expression
G1 R5 Expression ::= Number
G1 R6 Expression ::= '(' Expression ')'
G1 R7 Expression ::= Expression '**' Expression
G1 R8 Expression ::= Expression '*' Expression
G1 R9 Expression ::= Expression '/' Expression
G1 R10 Expression ::= Expression '+' Expression
G1 R11 Expression ::= Expression '-' Expression
G1 R12 :start ::= Script
L0 R0 comma ::= [,]
L0 R1 '(' ::= [\(]
L0 R2 ')' ::= [\)]
L0 R3 '**' ::= [\*] [\*]
L0 R4 '*' ::= [\*]
L0 R5 '/' ::= [\/]
L0 R6 '+' ::= [\+]
L0 R7 '-' ::= [\-]
L0 R8 Number ::= [\d] +
L0 R9 :discard ::= whitespace
L0 R10 whitespace ::= [\s] +
L0 R11 :discard ::= <hash comment>
L0 R12 <hash comment> ::= <terminated hash comment>
L0 R13 <hash comment> ::= <unterminated final hash comment>
L0 R14 <terminated hash comment> ::= [\#] <hash comment body> <vertical space char>
L0 R15 <unterminated final hash comment> ::= [\#] <hash comment body>
L0 R16 <hash comment body> ::= <hash comment char> *
L0 R17 <vertical space char> ::= [\x{A}\x{B}\x{C}\x{D}\x{2028}\x{2029}]
L0 R18 <hash comment char> ::= [^\x{A}\x{B}\x{C}\x{D}\x{2028}\x{2029}]
L0 R19 :start_lex ::= Number
L0 R20 :start_lex ::= :discard
L0 R21 :start_lex ::= '('
L0 R22 :start_lex ::= ')'
L0 R23 :start_lex ::= '**'
L0 R24 :start_lex ::= '*'
L0 R25 :start_lex ::= '/'
L0 R26 :start_lex ::= '+'
L0 R27 :start_lex ::= '-'
L0 R28 :start_lex ::= comma
END_OF_SHOW_RULES_OUTPUT
sub my_parser {
my ( $grammar, $p_input_string ) = @_;
my $recce = Marpa::R2::Scanless::R->new( { grammar => $grammar } );
$recce->read($p_input_string);
my $value_ref = $recce->value();
if ( not defined $value_ref ) {
die "No parse was found, after reading the entire input\n";
}
return ${$value_ref}->doit();
} ## end sub my_parser
my @tests = (
[ '42*2+7/3, 42*(2+7)/3, 2**7-3, 2**(7-3)' =>
qr/\A 86[.]3\d+ \s+ 126 \s+ 125 \s+ 16\z/xms
],
[ '42*3+7, 42 * 3 + 7, 42 * 3+7' => qr/ \s* 133 \s+ 133 \s+ 133 \s* /xms
],
[ '15329 + 42 * 290 * 711, 42*3+7, 3*3+4* 4' =>
qr/ \s* 8675309 \s+ 133 \s+ 25 \s* /xms
],
);
for my $test (@tests) {
my ( $input, $output_re ) = @{$test};
my $result = my_parser( $slg, \$input );
Test::More::like( $result, $output_re, 'Value of scannerless parse' );
}
sub My_Nodes::script::doit {
my ($self) = @_;
return join q{ }, map { $_->doit() } @{$self};
}
sub My_Nodes::add::doit {
my ($self) = @_;
my ( $a, $b ) = @{$self};
return $a->doit() + $b->doit();
}
sub My_Nodes::subtract::doit {
my ($self) = @_;
my ( $a, $b ) = @{$self};
return $a->doit() - $b->doit();
}
sub My_Nodes::multiply::doit {
my ($self) = @_;
my ( $a, $b ) = @{$self};
return $a->doit() * $b->doit();
}
sub My_Nodes::divide::doit {
my ($self) = @_;
my ( $a, $b ) = @{$self};
return $a->doit() / $b->doit();
}
sub My_Nodes::primary::doit { return $_[0]->[0]; }
sub My_Nodes::parens::doit { return $_[0]->[0]->doit(); }
sub My_Nodes::power::doit {
my ($self) = @_;
my ( $a, $b ) = @{$self};
return $a->doit()**$b->doit();
}
# vim: expandtab shiftwidth=4:
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