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#!perl
# Marpa::R3 is Copyright (C) 2017, Jeffrey Kegler.
#
# This module is free software; you can redistribute it and/or modify it
# under the same terms as Perl 5.10.1. For more details, see the full text
# of the licenses in the directory LICENSES.
#
# This program is distributed in the hope that it will be
# useful, but it is provided "as is" and without any express
# or implied warranties. For details, see the full text of
# of the licenses in the directory LICENSES.
# Note: This is leo3.t converted to the SLIF
# The example from p. 166 of Leo's paper,
# augmented to test Leo prediction items.
# Similar to other tests, but the focuses in this
# one are the Earley set counts and the
# diagnostics.
use 5.010001;
use strict;
use Test::More tests => 5;
use POSIX qw(setlocale LC_ALL);
POSIX::setlocale(LC_ALL, "C");
use lib 'inc';
## no critic (Subroutines::RequireArgUnpacking)
sub main::default_action {
return ( join q{}, grep {defined} @{$_[1]} );
}
## use critic
my $grammar = Marpa::R3::Scanless::G->new(
{
source => \(<<'END_OF_DSL'),
:default ::= action => main::default_action
:start ::= S
S ::= a A
A ::= B
B ::= C
C ::= S
S ::=
a ~ 'a'
END_OF_DSL
}
);
Marpa::R3::Test::is( $grammar->show_symbols(),
<<'END_OF_STRING', 'Leo166 Symbols' );
G1 S0 A
G1 S1 B
G1 S2 C
G1 S3 S
G1 S4 [:start]
G1 S5 a
END_OF_STRING
Marpa::R3::Test::is( $grammar->show_rules,
<<'END_OF_STRING', 'Leo166 Rules' );
G1 R0 S ::= a A
G1 R1 A ::= B
G1 R2 B ::= C
G1 R3 C ::= S
G1 R4 S ::=
G1 R5 [:start] ::= S
END_OF_STRING
Marpa::R3::Test::is( $grammar->show_ahms, <<'END_OF_STRING', 'Leo166 AHMs' );
AHM 0: postdot = "a"
S ::= . a A
AHM 1: postdot = "A"
S ::= a . A
AHM 2: completion
S ::= a A .
AHM 3: postdot = "a"
S ::= . a A[]
AHM 4: completion
S ::= a A[] .
AHM 5: postdot = "B"
A ::= . B
AHM 6: completion
A ::= B .
AHM 7: postdot = "C"
B ::= . C
AHM 8: completion
B ::= C .
AHM 9: postdot = "S"
C ::= . S
AHM 10: completion
C ::= S .
AHM 11: postdot = "S"
[:start] ::= . S
AHM 12: completion
[:start] ::= S .
AHM 13: postdot = "[:start]"
[:start]['] ::= . [:start]
AHM 14: completion
[:start]['] ::= [:start] .
END_OF_STRING
my $length = 20;
my $recce = Marpa::R3::Scanless::R->new(
{ grammar => $grammar } );
my $i = 0;
my $g1_pos = $recce->g1_pos();
my $max_size = $recce->earley_set_size($g1_pos);
$recce->read( \('a' x $length) );
TOKEN: for ( my $i = 0; $i < $length; $i++ ) {
my $size = $recce->earley_set_size($i);
$max_size = $size > $max_size ? $size : $max_size;
} ## end while ( $i++ < $length )
my $expected_size = 10;
Marpa::R3::Test::is( $max_size, $expected_size,
"Earley set size, got $max_size, expected $expected_size" );
my $value_ref = $recce->value();
my $value = $value_ref ? ${$value_ref} : 'No parse';
Marpa::R3::Test::is( $value, 'a' x $length, 'Leo p166 parse' );
# vim: expandtab shiftwidth=4: