chain abstract method

Function chain(covariant Function? a, covariant Function? b)

Returns a strongly-typed chained callback that calls through to the two provided callbacks, a and b, in order. Useful for executing multiple callbacks where only a single callback is accepted.

Returns false if one or more of the provided callbacks returns false.

Gracefully handles when a and/or b are null, always returning a callable function.

Implementation

Function chain(covariant Function? a, covariant Function? b);