scanner.py

#!/usr/bin/env python

from spark import GenericScanner
from token import Token
#
#	SCANNING
#

class SimpleScanner(GenericScanner):
	def __init__(self):
		GenericScanner.__init__(self)
	
	def tokenize(self, input):
		self.rv = []
		GenericScanner.tokenize(self, input)
		return self.rv
	
	def t_whitespace(self, s):
		r' \s+ '
		pass

	def t_fieldlabel(self, s):
		r' [\w]+: '
		self.rv.append(Token(type='string', attr=s))

	def t_bracket_open(self, s):
		r' { '
		self.rv.append(Token(type='bracket_op', attr=s))

	def t_bracket_close(self, s):
		r' [ ]?} '
		self.rv.append(Token(type='bracket_cl', attr=s))

	def t_form(self, s):
		r' form '
		self.rv.append(Token(type='Form', attr=s))

	def t_field_question(self, s):
		r' \'[\w\d\?/ ]+\' '
		self.rv.append(Token(type='string', attr=s))

	def t_formname(self, s):
		r' [\w\d]+ '
		self.rv.append(Token(type='FormName', attr=s))

	def t_boolean(self, s):
		r' boolean '
		self.rv.append(Token(type='bool', attr=s))


class CalculatorScanner(GenericScanner):

	def __init__(self):
		GenericScanner.__init__(self)
	
	def tokenize(self, input):
		self.rv = []
		GenericScanner.tokenize(self, input)
		return self.rv

	def t_whitespace(self, s):
		r' \s+ '
		pass

	def t_op(self, s):
		r' \+ | \* '
		self.rv.append(Token(type=s))

	def t_number(self, s):
		r' \d+ '
		t = Token(type='number', attr=s)
		self.rv.append(t)

	# Implementation of "add" and "mod" tokens.
	def t_add(self, s):
		r' add '
		self.rv.append(Token(type=s))

	def t_mod(self, s):
		r' mod '
		self.rv.append(Token(type=s))

class FloatScanner(CalculatorScanner):
	def __init__(self):
		CalculatorScanner.__init__(self)
		
	def t_float(self, s):
		r' \d+ \. \d+ '
		t = Token(type='float', attr=s)
		self.rv.append(t)



def scan(f):
	input_contents = f.read()
	# scanner = FloatScanner()
	scanner = SimpleScanner()
	return scanner.tokenize(input_contents)