lcfOS: python/pyyacc.py comparison

Added assembler testset

comparison

equal deleted inserted replaced

-:65dda7e7e8bd
+:6b2bec5653f1
 """
 Parser generator script
 """
+from ppci import Token
 EPS = 'EPS'
 EOF = 'EOF'
 SHIFT = 1
 REDUCE = 2
 def __init__(self, action_table, goto_table):
 self.action_table = action_table
 self.goto_table = goto_table
 def parse(self, toks):
+""" Parse an iterable with tokens """
+assert hasattr(toks, '__iter__'), '{0} not iter type'.format(type(toks))
 stack = [0]
-look_ahead = toks.pop(0)
+look_ahead = toks.__next__()
+assert type(look_ahead) is Token
 while True:
 state = stack[-1]   # top of stack
-key = (state, look_ahead)
+key = (state, look_ahead.typ)
 if not key in self.action_table:
-print(key)
+raise Exception('Error parsing at character {0}'.format(look_ahead))
-raise Exception('Error parsing')
+action, param = self.action_table[key]
-action, param = self.action_table[(state, look_ahead)]
 if action == REDUCE:
 for s in param.symbols:
 stack.pop()
 stack.pop()
 state = stack[-1]
 stack.append(param.name)
 stack.append(self.goto_table[(state, param.name)])
 elif action == SHIFT:
-stack.append(look_ahead)
+stack.append(look_ahead.typ)
 stack.append(param)
-look_ahead = toks.pop(0)
+try:
+look_ahead = toks.__next__()
+except StopIteration:
+look_ahead = Token(EOF, EOF, 0)
+assert type(look_ahead) is Token
 elif action == ACCEPT:
 break
 def testSimpleGrammar():
 # 1. define a simple grammar:

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