Member Patterns -- the bikeshed

[Attila Kelemen]

>
> Lambdas.  A SAM interface is one with a single abstract method, and we
> extract the function shape and use it as a target type for lambdas.
> Similarly, a SAP interface is one with a single abstract pattern.  We can
> play the same game, except the shape is (match candidate) -> { pattern body
> that binds declared bindings }.  This allows APIs to be extend with
> patterns, such as a `match` method in streams:
>
>       objects.stream().match(e -> e instanceof String s)....
>
> where Stream::match takes a SAP interface with a single binding, such as:
>
>     interface Matchy<T, U> {
>         pattern(T that) p(U u);
>     }
> ...
>     // in Stream
>     <U> Stream<U> match(Matchy<T,U> m);
>

I see, thanks. What I was missing is that I thought a "pattern" method
cannot exist without its pair. And that explains why wasn't the short
"inverse" syntax chosen: Because the fact that the "pattern" method has the
same name / types is just a coincidence from the point of view of the
compiler (hopefully I'm not misunderstanding something again).
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