T - the type of the input variableV - the type of the outputpublic interface PartialFunction<T,V>
PartialFunction is,
like the mathematical concept of the same name, not defined over all possible inputs,
and can therefore throw Exceptions. The function itself should return
immediately and, if a blocking process is needed, launch that process and return
a Future handle. If the code implementing apply does
not throw a checked exception consider using Function.Function,
PartialFuture