forax at univ-mlv.fr
Sat Nov 23 03:17:53 PST 2013
On 11/23/2013 02:32 AM, Brian Goetz wrote:
> Function is extended by BinaryOperator, also a functional interface,
> which specializes its type parameters. I think that's a fine pattern.
I don't want to restart the thread about the naming of UnaryOperator and
but BinaryOperator is a BiFunction not a Function, UnaryOperator is a
BTW I've recently discover something weird, Function.identity() should
return a UnaryOperator<T> and not a Function<T,T> which can be seen as
an hint of the fact that having two interfaces for something so similar
is not a good idea.
I think we have missed a point when we have discussed about naming, the
real question is why UnaryOperator and BinaryOperator exist, from now,
they does not seem to worth their weight (naming, specialization, etc) ?
> More generally, its perfectly fine for an interface to extend a
> functional interface but not itself be a functional interface. See
> Node.Builder inside the Stream package, for example.
> On 11/22/2013 7:50 PM, Richard Warburton wrote:
>> If the intent of an interface marked with @FunctionalInterface is to be
>> used as such then should it ever be extended by another interface?
>> I appreciate there are probably enough complex interactions that generating
>> a compile error if this happens would be too restrictive but what about
>> 'morally' or as a guideline?
>> Richard Warburton
>> @RichardWarburto <http://twitter.com/richardwarburto>
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