def test_fails_to_parse_non_ll1(self):
e = self.assertSimpleParseFailure(
combinators.choice(
combinators.sequence(primitives.match(lambda c: c == "h"),
primitives.match(lambda c: c == "a")),
combinators.sequence(primitives.match(lambda c: c == "b"),
primitives.match(lambda c: c == "e"))),
"hello")
self.assertEqual("e", e.value)
self.assertEqual(list("llo"), list(e.it))
self.assertEqual(set(), e.expected)
def word(s):
"""Parse a sequence of characters as a single string.
Args:
s: Allowed characters in the word.
Returns:
The parsing function.
"""
@combinators.mapf(combinators.many1(one_of(s)))
def _action(cs):
return "".join(cs)
return combinators.choice(_action, primitives.error(list(s)))
def literal(s):
"""Parse a predefined literal.
Args:
s: The literal to parse.
Returns:
The parsing function.
"""
@combinators.mapf(combinators.sequence(*[char(c) for c in s]))
def _action(cs):
return "".join(cs)
return combinators.choice(combinators.suppress_expect(_action),
primitives.error([s]))
def __or__(self, rhs):
return Parser(combinators.choice(self, rhs))
def test_fails_to_parse(self):
e = self.assertParseFailure(
combinators.choice(primitives.error({"error1!"}),
primitives.error({"error2!"})),
"hello")
self.assertEqual({"error1!", "error2!"}, e.expected)
def test_parses_second(self):
self.assertParse(
combinators.choice(primitives.match(lambda c: c == "h"),
primitives.match(lambda c: c == "y")),
"y", "ello", "yello")
def test_parses(self):
self.assertParse(
combinators.choice(primitives.match(lambda c: c == "h"),
primitives.match(lambda c: c == "a")),
"h", "ello", "hello")
