# The parser for reading ILOC instruction files.
import sys
from util import Instruction

class ILOCParser(object):
	"""
	A parser for ILOC instruction files.
	"""
	def __init__(self, file):
		self.inputFile = open(file)

	def parse(self):
		instructionList = []
		for line in self.inputFile:
			if line[-1] == "\n":
				line = line[:-1]
			if "//" in line:
				line = line[:line.index("//")] # remove comments
			line = line.strip() # strip whitespace at beginning and end
			if line == "": # line has no instructions
				continue
			line = line.replace(",", " ") # remove commas
			line = line.replace("=>", " ") # remove arrows
			line = line.split()
			instructionList.append(Instruction(line[0], line[1:]))
		return instructionList