def __init__(self, grammar, ruleName, callback=None, globals=None):
self.grammar = grammar
self.position = 0
self.callback = callback
self.globals = globals or {}
self.rules = decomposeGrammar(grammar)
self.next = self.apply(ruleName, None, ())
self._localsStack = []
self.currentResult = None
self.input = InputStream([], 0)
self.ended = False
