def _cast_to_type_if_compatible()

in models/src/wavenet_vocoder/tfcompat/hparam.py [0:0]

• 21 lines of code
• 12 McCabe index (conditional complexity)

def _cast_to_type_if_compatible(name, param_type, value):
    """Cast hparam to the provided type, if compatible.

    Args:
      name: Name of the hparam to be cast.
      param_type: The type of the hparam.
      value: The value to be cast, if compatible.

    Returns:
      The result of casting `value` to `param_type`.

    Raises:
      ValueError: If the type of `value` is not compatible with param_type.
        * If `param_type` is a string type, but `value` is not.
        * If `param_type` is a boolean, but `value` is not, or vice versa.
        * If `param_type` is an integer type, but `value` is not.
        * If `param_type` is a float type, but `value` is not a numeric type.
    """
    fail_msg = "Could not cast hparam '%s' of type '%s' from value %r" % (
        name,
        param_type,
        value,
    )

    # Some callers use None, for which we can't do any casting/checking. :(
    if issubclass(param_type, type(None)):
        return value

    # Avoid converting a non-string type to a string.
    if issubclass(param_type, (six.string_types, six.binary_type)) and not isinstance(
        value, (six.string_types, six.binary_type)
    ):
        raise ValueError(fail_msg)

    # Avoid converting a number or string type to a boolean or vice versa.
    if issubclass(param_type, bool) != isinstance(value, bool):
        raise ValueError(fail_msg)

    # Avoid converting float to an integer (the reverse is fine).
    if issubclass(param_type, numbers.Integral) and not isinstance(
        value, numbers.Integral
    ):
        raise ValueError(fail_msg)

    # Avoid converting a non-numeric type to a numeric type.
    if issubclass(param_type, numbers.Number) and not isinstance(value, numbers.Number):
        raise ValueError(fail_msg)

    return param_type(value)