tf.compat.v1.flags.register_validator

Adds a constraint, which will be enforced during program execution.

Compat aliases for migration

`tf.compat.v1.app.flags.register_validator`

tf.compat.v1.flags.register_validator(
    flag_name,
    checker,
    message='Flag validation failed',
    flag_values=_flagvalues.FLAGS
)

The constraint is validated when flags are initially parsed, and after each change of the corresponding flag's value.

Args
`flag_name`	str \| FlagHolder, name or holder of the flag to be checked. Positional-only parameter.
`checker`	callable, a function to validate the flag. input - A single positional argument: The value of the corresponding flag (string, boolean, etc. This value will be passed to checker by the library). output - bool, True if validator constraint is satisfied. If constraint is not satisfied, it should either `return False` or `raise flags.ValidationError(desired_error_message)`.
`message`	str, error text to be shown to the user if checker returns False. If checker raises flags.ValidationError, message from the raised error will be shown.
`flag_values`	flags.FlagValues, optional FlagValues instance to validate against.

Raises
`AttributeError`	Raised when flag_name is not registered as a valid flag name.
`ValueError`	Raised when flag_values is non-default and does not match the FlagValues of the provided FlagHolder instance.

Args