Any top-level constant

_Any const Any

Any takes a key and an arbitrary values and choose the one that fits.

Note that the Any unlike other particular types of Field is not a subclass of it, but rather an instance of callable class that is designed to mimic Field's API.

As Any makes runtime type checking make sure that it is used only where it is necessary, otherwise use one of predefined fields.

Implementation

// ignore:constant_identifier_names
const _Any Any = _Any();