Esempio n. 1
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def map_type_from_supertype(typ: Type, sub_info: TypeInfo,
                            super_info: TypeInfo) -> Type:
    """Map type variables in a type defined in a supertype context to be valid
    in the subtype context. Assume that the result is unique; if more than
    one type is possible, return one of the alternatives.

    For example, assume

    . class D(Generic[S]) ...
    . class C(D[E[T]], Generic[T]) ...

    Now S in the context of D would be mapped to E[T] in the context of C.
    """
    # Create the type of self in subtype, of form t[a1, ...].
    inst_type = fill_typevars(sub_info)
    if isinstance(inst_type, TupleType):
        inst_type = inst_type.fallback
    # Map the type of self to supertype. This gets us a description of the
    # supertype type variables in terms of subtype variables, i.e. t[t1, ...]
    # so that any type variables in tN are to be interpreted in subtype
    # context.
    inst_type = map_instance_to_supertype(inst_type, super_info)
    # Finally expand the type variables in type with those in the previously
    # constructed type. Note that both type and inst_type may have type
    # variables, but in type they are interpreted in supertype context while
    # in inst_type they are interpreted in subtype context. This works even if
    # the names of type variables in supertype and subtype overlap.
    return expand_type_by_instance(typ, inst_type)
Esempio n. 2
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def map_type_from_supertype(typ: Type, sub_info: TypeInfo,
                            super_info: TypeInfo) -> Type:
    """Map type variables in a type defined in a supertype context to be valid
    in the subtype context. Assume that the result is unique; if more than
    one type is possible, return one of the alternatives.

    For example, assume

    . class D(Generic[S]) ...
    . class C(D[E[T]], Generic[T]) ...

    Now S in the context of D would be mapped to E[T] in the context of C.
    """
    # Create the type of self in subtype, of form t[a1, ...].
    inst_type = fill_typevars(sub_info)
    if isinstance(inst_type, TupleType):
        inst_type = inst_type.fallback
    # Map the type of self to supertype. This gets us a description of the
    # supertype type variables in terms of subtype variables, i.e. t[t1, ...]
    # so that any type variables in tN are to be interpreted in subtype
    # context.
    inst_type = map_instance_to_supertype(inst_type, super_info)
    # Finally expand the type variables in type with those in the previously
    # constructed type. Note that both type and inst_type may have type
    # variables, but in type they are interpreted in supertype context while
    # in inst_type they are interpreted in subtype context. This works even if
    # the names of type variables in supertype and subtype overlap.
    return expand_type_by_instance(typ, inst_type)
Esempio n. 3
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def class_callable(init_type: CallableType, info: TypeInfo, type_type: Instance,
                   special_sig: Optional[str]) -> CallableType:
    """Create a type object type based on the signature of __init__."""
    variables = []  # type: List[TypeVarDef]
    variables.extend(info.defn.type_vars)
    variables.extend(init_type.variables)

    callable_type = init_type.copy_modified(
        ret_type=fill_typevars(info), fallback=type_type, name=None, variables=variables,
        special_sig=special_sig)
    c = callable_type.with_name('"{}"'.format(info.name()))
    c.is_classmethod_class = True
    return c
Esempio n. 4
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def class_callable(init_type: CallableType, info: TypeInfo,
                   type_type: Instance,
                   special_sig: Optional[str]) -> CallableType:
    """Create a type object type based on the signature of __init__."""
    variables = []  # type: List[TypeVarDef]
    variables.extend(info.defn.type_vars)
    variables.extend(init_type.variables)

    callable_type = init_type.copy_modified(ret_type=fill_typevars(info),
                                            fallback=type_type,
                                            name=None,
                                            variables=variables,
                                            special_sig=special_sig)
    c = callable_type.with_name('"{}"'.format(info.name()))
    c.is_classmethod_class = True
    return c