Re: [RFC:generics]

On 4/20/16 10:01 AM, Rowan Collins wrote:

guilhermeblanco@gmail.com wrote on 20/04/2016 03:54:

1- Even though mentioned, I'd still use "extends" or "implements" instead of "is" (which would be a new pseudo-reserved keyword) to enforce data type consistency and prevent developers to potentially referring to one thing while consider another.

Perhaps "instanceof" would make more sense here? "class FileProcessor<T extends FileHandle>" seems to exclude instantiating FileProcessor<FileHandle>, because "FileHandle extends FileHandle" doesn't make any sense. You could read "class Box<T instanceof Boxable>" as an assertion that the class passes the constraint, as in "public function __construct(T $t) { assert($t instanceof Boxable); }" Regards,

I'm not an expert in generics by any means, but how is that different than just public function __construct(Boxable $t) {} I thought the point of generics was for cases like "these two variables must be the same type, but they can be any same type." -- --Larry Garfield