def infer_type(expr, scope):
"""Try to infer the type of x.y if y is a known value (literal)."""
# Do we know what the member is?
if isinstance(expr.member, ast.Literal):
member = expr.member.value
else:
return protocol.AnyType
container_type = infer_type(expr.obj, scope)
try:
# We are not using lexical scope here on purpose - we want to see what
# the type of the member is only on the container_type.
return structured.reflect(container_type, member) or protocol.AnyType
except NotImplementedError:
return protocol.AnyType
def solve_isinstance(expr, vars):
"""Typecheck whether LHS is type on the RHS."""
lhs = solve(expr.lhs, vars)
t = structured.reflect(vars, expr.rhs)
return Result(protocol.implements(lhs.value, t), ())
