def test_complex_operation(self):
two = Operation(OperationType.POSITIVE(), [Variable(2)])
negative_x = Operation(OperationType.NEGATIVE(), [Variable('x')])
op = Operation(OperationType.TIMES(), [two, negative_x])
verify(str(op), self.reporter)
def test_equation(self):
two = Operation(OperationType.POSITIVE(), [Variable(2)])
negative_x = Operation(OperationType.NEGATIVE(), [Variable('x')])
lhs = Operation(OperationType.TIMES(), [two, negative_x])
rhs = Variable(3.1415)
eq = Equation(lhs, rhs)
verify(str(eq), self.reporter)
class PrefixParselet:
token_map = {
TokenType.PLUS : OperationType.POSITIVE(),
TokenType.MINUS : OperationType.NEGATIVE()
}
def __init__(self, token):
assert isinstance(token, Token)
if token.token_type in self.token_map.keys():
self._operation_type = self.token_map[token.token_type]
else:
self._operation_type = OperationType.VARIABLE(token.value)
def parse(self, parser):
assert isinstance(parser, Parser)
if self._operation_type in self.token_map.values():
right = parser.parse(precedence=10) # All prefixes should be evaluated before infixes
return Operation(self._operation_type, [right])
else:
return Operation(self._operation_type)