grammar.py

import parser
from parser import *

def enable_debug():
	myparser.DEBUG_DEFAULT = True

def joiner(l):
	return ''.join(l)

chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
digits = '0123456789'
hex_digits = digits + 'abcdefABCDEF'
spaces = ' \t'
newlines = '\n\r'

hex_number = LinearMatch(StringMatch('0x').postprocess(joiner), Word(hex_digits)).combine()
number = LinearMatch(atom('-').optional(), Word(digits)).combine().name('number').nameonly()
whitespace = Word(spaces + newlines).hide()
register = LinearMatch(atom('$'), Word(chars + digits)).combine().name('register').nameonly()
address = hex_number.name('address').nameonly()
offset = (number + whitespace.optional() + atom('(').hide() + (register | address) + atom(')').hide()).combine()

instruction_delimiter = whitespace.optional() + atom(',').hide() + whitespace.optional()
instruction_start = (whitespace.optional() + Word(chars + digits).name('instruction-name').nameonly() + whitespace).combine()
instruction = LinearMatch(instruction_start, DelimitedMatch((register | offset | hex_number | address | number).combine(), whitespace.optional() + atom(',') + whitespace.optional())).combine()

r_instruction = register + instruction_delimiter + register + instruction_delimiter + register
i_instruction = register + instruction_delimiter + register + instruction_delimiter + (number | hex_number)
j_instruction = address

comment = LinearMatch(OrMatch(atom(';'), atom('#')), StarMatch(NotMatch(orstring(newlines))))
end_of_instruction = LinearMatch(whitespace.optional(), comment.optional(), StarMatch(orstring(newlines), min=1)).combine()
#end_of_instruction = LinearMatch(comment.optional(), StarMatch(orstring(newlines), min=1)).combine()

#instructions = (DelimitedMatch(instruction, end_of_instruction).combine() + StarMatch(orstring('\n\t\r ')).hide()).combine()
line = LinearMatch(instruction.optional(), Word(spaces).hide().optional(), comment.optional().hide()).combine()
instructions = DelimitedMatch(line, orstring(newlines)).combine()

def parse(insts):
	return totalMatch(insts, instructions)

def raw_parse(insts):
	return instructions.match(insts)

if __name__ == '__main__':
	import unittest

	class Tests(unittest.TestCase):
		def test_instructions(self):
			self.assertEquals(totalMatch("""ori $r1, $r0, 1 #test
addi $r2, $r0, 2""", instructions), [['ori', [['$', 'r1'], ['$', 'r0'], ['1']]],
 									 ['addi', [['$', 'r2'], ['$', 'r0'], ['2']]]])
 	
 	unittest.main()