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#!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/.
use 5.010001;
# A variation on
# the example grammar in Aycock/Horspool "Practical Earley Parsing",
# _The Computer Journal_, Vol. 45, No. 6, pp. 620-630,
# Its order of ambiguity generates Pascal's triangle.
use strict;
use warnings;
use Test::More tests => 10;
use lib 'inc';
use Marpa::R2::Test;
use Marpa::R2;
my $n = 10;
my $dsl = <<'=== END_OF_DSL ===';
:default ::= action => [name,values]
lexeme default = latm => 1
sequence ::= A action => main::one
| A sequence action => main::add
A ::= 'a' action => main::one
=== END_OF_DSL ===
sub one { return 1 }
sub add { my (undef, $left, $right) = @_;
# say STDERR join " ", "args:", @_;
return $left+$right }
my $grammar = Marpa::R2::Scanless::G->new( { source => \$dsl } );
my $recce = Marpa::R2::Scanless::R->new( { grammar => $grammar } );
my $input = 'a' x $n;
$recce->read( \$input, 0, 0 );
my @parse_counts = (1);
for my $loc ( 1 .. $n ) {
my $parse_number = 0;
$recce->series_restart();
$recce->resume( undef, 1 );
die "No parse" if not my $value_ref = $recce->value();
local $Data::Dumper::Deepcopy = 1;
# say STDERR Data::Dumper::Dumper($value_ref);
my $actual = ${$value_ref};
Marpa::R2::Test::is( $actual, $loc,
"Count $loc of incremental read" );
} ## end for my $loc ( 1 .. $n )
1; # In case used as "do" file
# Local Variables:
# mode: cperl
# cperl-indent-level: 4
# fill-column: 100
# End:
# vim: set expandtab shiftwidth=4:
|
