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|
use strict;
use warnings;
use lib qw( t/lib );
use Test::More;
use ANTLR::Runtime::Test;
plan tests => 1;
# The SimpleCalc grammar from the five minutes tutorial.
g_test_output_is({ grammar => <<'GRAMMAR', test_program => <<'CODE', expected => <<'OUTPUT' });
grammar Expr;
options { language = Perl5; }
@header {}
@members {
my %memory;
}
prog: stat+ ;
stat: expr NEWLINE { print "$expr.value\n"; }
| ID '=' expr NEWLINE
{ $memory{$ID.text} = $expr.value; }
| NEWLINE
;
expr returns [value]
: e=multExpr { $value = $e.value; }
( '+' e=multExpr { $value += $e.value; }
| '-' e=multExpr { $value -= $e.value; }
)*
;
multExpr returns [value]
: e=atom { $value = $e.value; } ('*' e=atom { $value *= $e.value; })*
;
atom returns [value]
: INT { $value = $INT.text; }
| ID
{
my $v = $memory{$ID.text};
if (defined $v) {
$value = $v;
} else {
print STDERR "undefined variable $ID.text\n";
}
}
| '(' expr ')' { $value = $expr.value; }
;
ID : ('a'..'z'|'A'..'Z')+ ;
INT : '0'..'9'+ ;
NEWLINE:'\r'? '\n' ;
WS : (' '|'\t')+ { $self->skip(); } ;
GRAMMAR
use strict;
use warnings;
use ANTLR::Runtime::ANTLRStringStream;
use ANTLR::Runtime::CommonTokenStream;
use ExprLexer;
use ExprParser;
my $in = << 'EOT';
1 + 1
8 - 1
a = 10
b = 13
2 * a + b + 1
EOT
my $input = ANTLR::Runtime::ANTLRStringStream->new({ input => $in });
my $lexer = ExprLexer->new({ input => $input });
my $tokens = ANTLR::Runtime::CommonTokenStream->new({ token_source => $lexer });
my $parser = ExprParser->new({ input => $tokens });
$parser->prog();
CODE
2
7
34
OUTPUT
|
