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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/.
# This test is mainly a place to record his "dwim" function,
# which Jeffrey keeps losing track of.
# The DWIM (Do What I Mean) action is intended to be used as
# a default action. It looks at the values
# of each rule and gives you a compact first cut,
# which is reasonably likely to turn out to be
# what you want to do with the rule.
# The example is based on the smaller minimal working example
# for Libmarpa issue 115 (Dave Abrahams).
use 5.010001;
use strict;
use warnings;
use Scalar::Util;
use Data::Dumper;
use Test::More tests => 1;
use lib 'inc';
use Marpa::R2::Test;
## no critic (ErrorHandling::RequireCarping);
use Marpa::R2;
my $bnf = <<'END_OF_BNF';
:default ::= action => main::dwim
lexeme default = latm => 1
:start ::= prefixExpr
prefixExpr ::= null prefixExpr Arg2
prefixExpr ::= Arg1
null ::=
:discard ~ whitespace
unicorn ~ [^\d\D]
whitespace ~ [\s]+
Arg1 ~ unicorn
Arg2 ~ unicorn
END_OF_BNF
my $grammar = Marpa::R2::Scanless::G->new(
{
source => \$bnf,
}
);
my $string = <<'EOS';
type A {
var a: Int
fun foo(a: Int) { a.copy() }
fun foo(b: Int) -> Int {
let { a + b }
inout { b += a }
}
}
EOS
my $recce = Marpa::R2::Scanless::R->new( { grammar => $grammar } );
$recce->read( \$string, 0, 0 );
if ( not defined $recce->lexeme_read( 'Arg1', undef, 1, 'Arg1' ) ) {
die qq{Parser rejected token "Arg1"};
}
if ( not defined $recce->lexeme_read( 'Arg2', undef, 1, 'Arg2' ) ) {
die qq{Parser rejected token "Arg2"};
}
if ( not defined $recce->lexeme_read( 'Arg2', undef, 1, 'Arg2' ) ) {
die qq{Parser rejected token "Arg2"};
}
my $value_ref = $recce->value();
if ( not defined $value_ref ) {
die "No parse was found, after reading the entire input\n";
}
my $expected_value = \[ [ 'Arg1', 'Arg2' ], 'Arg2' ];
Test::More::is_deeply(
Data::Dumper::Dumper($value_ref),
Data::Dumper::Dumper($expected_value),
'Value of parse'
);
sub main::dwim {
my @result = ();
shift;
ARG: for my $v ( @_ ) {
next ARG if not $v;
my $type = Scalar::Util::reftype $v;
if (not $type or $type ne 'ARRAY') {
push @result, $v;
next ARG;
}
my $size = scalar @{$v};
next ARG if $size == 0;
if ($size == 1) {
push @result, ${$v}[0];
next ARG;
}
push @result, $v;
}
return [@result];
}
# vim: expandtab shiftwidth=4:
|
