gistfile1.txt

grammar Grmmr
{
	rule TOP
	{
		<suite>
		{*}
	};
	token suite
	{
		<var_stmt> \n <var_stmt>
		{*}
	};
	token var_stmt
	{
		'var ' <identifier> ' ' <assignoperator> ' ' <expression>
		{*}
	};
	token identifier
	{
		<[a..z]> \w*
		{*}
	};
	token assignoperator
	{
		| '=' {*}	#= assign
		| '+=' {*}	#= add
		| '-=' {*}	#= sub
		| '*=' {*}	#= mul
		| '/=' {*}	#= div
		| '\%=' {*}	#= mod
		| '||=' {*}	#= or
		| '&&=' {*}	#= and
	};
	token expression
	{
		<or_test>
		{*}
	};
	token or_test
	{
		<xor_test> [ 'or' <xor_test> ]*
		{*}
	};
	token xor_test
	{
		<and_test> [ 'xor' <and_test> ]*
		{*}
	};
	token and_test
	{
		<not_test> [ 'and' <not_test> ]*
		{*}
	};
	token not_test
	{
		['not']? <comparison>
		{*}
	};
	token comparison
	{
		<variable> ** <operator>
		{*}
	};
	token variable
	{
		| <identifier> {*}	#= identifier
		| <number> {*}		#= number
		| <string> {*}		#= string
	};
	token number
	{
		\d+ [ '.' \d+ ]? {*}
	};
	token string
	{
		'"' .* '"' {*}
	};
	token operator
	{
		| '~' {*}	#= concat
		| '+' {*}	#= plus
		| '-' {*}	#= sub
		| '*' {*}	#= mul
		| '/' {*}	#= div
		| '%' {*}	#= mod
		| '==' {*}	#= eq
		| '!=' {*}	#= ne
		| '<=' {*}	#= leq
		| '>=' {*}	#= geq
		| '<' {*}	#= lt
		| '>' {*}	#= gt
	};
};

my $action = Actions.new(); Grmmr.parse("var alpha = 3 + 8\nvar beta += 7", :action($action));