[swift-dev] A type-checking performance case study

[Dmitri Gribenko]

On Fri, Apr 8, 2016 at 11:47 AM, John McCall via swift-dev
<swift-dev at swift.org> wrote:
> I strongly recommend that we pursue declaration hiding as a language change.

I completely agree with John.  Not having this rule is not just a
performance problem, it also leaks into the user model.  For example:

- If you have a lazy collection, you can still call the eager `map` if
you provide matching type context.

- If a protocol extension method that was intended to be a default
implementation does not get selected as the implementation, then both
are visible on the type.  This causes ambiguities when chaining.

Dmitri

-- 
main(i,j){for(i=2;;i++){for(j=2;j<i;j++){if(!(i%j)){j=0;break;}}if
(j){printf("%d\n",i);}}} /*Dmitri Gribenko <gribozavr at gmail.com>*/