#
# Calc.yp
# 
# Parse::Yapp input grammar example.
#
# This file is PUBLIC DOMAIN 
#
#
%{
use Config::Irssi::Lexer;
%}
%right ','
%%
input:  #empty
        |   input line  { push(@{$_[1]},$_[2]); $_[1] }
;

line:       ';'   { $_[1] }
        |   toplevel
		|	error ';' { $_[0]->YYErrok }
;

toplevel: assign_list {
	my %hash = @{$_[1]};
	$_[0]->YYData->{return} = \%hash;
};

array: '(' list ')' { $_[2] }
     |  '(' list ',' ')' { $_[2] }
     | '(' ')' { [] };
hash:  '{' assign_list '}' { my %hash = @{$_[2]}; \%hash  }
    | '{' '}' { my %hash; \%hash };

assign: key '=' expr { [$_[1], $_[3]] };

assign_list: assign { [ @{$_[1]} ] }
           | assign ';' { [ @{$_[1]} ] }
           | assign ';' assign_list { [ @{$_[1]}, @{$_[3]} ] }
           | assign ';' assign_list ';' { [ @{$_[1]}, @{$_[3]} ] }
;

list: expr   { [ $_[1] ] }
         | expr ',' list  {
			[ $_[1], @{$_[3]} ];
		 }
;

key: SYMBOL | NUMBER | STRING;
expr: STRING | NUMBER | array | hash;


%%

sub error {
	my ($me) = @_;
	
	print "Oh, error\n";
	return if $me->YYData->{error};

	$me->YYData->{error} = {
		val => scalar $me->YYCurval,
		tok => scalar $me->YYCurtok,
		expect => [$me->YYExpect],
		line  => $.,
	};

	return;
}

sub parse {
    my ($self, $fh) = @_;
	
	$self->YYData->{fh} = $fh;
    $self->YYParse( yylex => mklexer($fh), yyerror => \&error );

	if ($self->YYData->{return}) {
		return $self->YYData->{return};
	}
	return undef;
}

sub lex {
    my ($self, $fh) = @_;
	
	$self->YYData->{fh} = $fh;
	while (my ($tok, $val) = $self->lexer) {
		last if (not $tok and not defined $val);
		print "# $tok";
		if ($val ne $tok) {
			print " ($val)";
		}
		print "\n";
	}
}