genTest.pijnu

# a mini test grammar for the generator

genTest

<toolset>
def doMult(node):
	(a,b) = node
	node.value = a.value * b.value

def doAdd(node):
	(a,b) = node
	node.value = a.value + b.value

def formatResult(node):
	node.value = "%.3f" % node.value
<definition>
# constants
	SPACE		: ' '							: drop
	SPACING		: SPACE*						: drop
	DOT			: "."
	MINUS		: "-"
	PLUS		: "+"							: drop
	ADD			: PLUS
	_ADD_		: SPACING ADD SPACING			: drop
	MULT		: "*"
	_MULT_		: SPACING MULT SPACING			: drop
	DIGIT		: [0..9]
	SIGN		: PLUS / MINUS
	SIGN_		: SIGN SPACING
	LPAREN		: "("							: drop
	RPAREN		: ")"							: drop

# operand
	digits		: DIGIT+
	integer		: SIGN_? digits
	real		: integer (DOT digits)?
	number		: real / integer				: join toFloat
	group		: LPAREN operation RPAREN		: liftNode
	operand 	: group / number

# operation
	mult		: operand _MULT_ (mult/operand)	: @ doMult
	addOp		: mult / operand
	add			: addOp _ADD_  (add/addOp)		: @ doAdd
	operation	: add / mult					: @
	foo			: ("a"/"b"){3}
	bar			: [1..9]{3}
	baz			: '1'{3}
	result		: operation / operand			: formatResult