def test_parse_with_ambiguity(self):
# Define new rules
rules = ['S->NP | VP', 'NP->book', 'VP->book']
earley = EarleyParser(Grammar(rules))
earley.parse('book')
self.assertIn(State(earley.DUMMY_CHAR,['S'],1,0,1), earley.chart[1])
self.assertIn(State('S',['NP'],1,0,1), earley.chart[1])
self.assertIn(State('S',['VP'],1,0,1), earley.chart[1])
self.assertItemsEqual([Tree('S', [Tree('NP', ['book'])]), Tree('S', [Tree('VP', ['book'])])], earley.tree())
print earley.tree()
def setUp(self):
rules = [
'S -> NP VP',
'NP -> Det N',
'VP -> VT NP',
'VP -> VI PP',
'PP -> P NP',
'Det -> a',
'N -> circle | square | triangle',
'VT -> touches',
'VI -> is',
'P -> above | below'
]
grammar = Grammar(rules)
self.earley = EarleyParser(grammar)
self.earley.words = 'a circle touches a triangle'.split(' ')
self.earley.chart = [[] for _ in range(5)]
