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#!/usr/bin/perl
# Copyright 2022 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 DSL pod of SLIF
use 5.010001;
use strict;
use warnings;
use Test::More tests => 3;
use English qw( -no_match_vars );
use Scalar::Util;
use lib 'inc';
use Marpa::R2::Test;
## no critic (ErrorHandling::RequireCarping);
# Marpa::R2::Display
# name: SLIF DSL synopsis
use Marpa::R2;
my $grammar = Marpa::R2::Scanless::G->new(
{ bless_package => 'My_Nodes',
source => \(<<'END_OF_SOURCE'),
:default ::= action => [values] bless => ::lhs
lexeme default = action => [ start, length, value ]
bless => ::name latm => 1
:start ::= Script
Script ::= Expression+ separator => comma
comma ~ [,]
Expression ::=
Number bless => primary
| '(' Expression ')' bless => paren assoc => group
|| Expression '**' Expression bless => exponentiate assoc => right
|| 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::End
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 $value = my_parser( $grammar, \$input );
Test::More::like( $value, $output_re, 'Value of scannerless parse' );
}
package My_Nodes;
sub My_Nodes::primary::doit { return $_[0]->[0]->doit() }
sub My_Nodes::Number::doit { return $_[0]->[2] }
sub My_Nodes::paren::doit { my ($self) = @_; $self->[1]->doit() }
sub My_Nodes::add::doit {
my ($self) = @_;
$self->[0]->doit() + $self->[2]->doit();
}
sub My_Nodes::subtract::doit {
my ($self) = @_;
$self->[0]->doit() - $self->[2]->doit();
}
sub My_Nodes::multiply::doit {
my ($self) = @_;
$self->[0]->doit() * $self->[2]->doit();
}
sub My_Nodes::divide::doit {
my ($self) = @_;
$self->[0]->doit() / $self->[2]->doit();
}
sub My_Nodes::exponentiate::doit {
my ($self) = @_;
$self->[0]->doit()**$self->[2]->doit();
}
sub My_Nodes::Script::doit {
my ($self) = @_;
return join q{ }, map { $_->doit() } @{$self};
}
# vim: expandtab shiftwidth=4:
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