DIP 1009--Improve Contract Usability--Preliminary Review Round 1

[Moritz Maxeiner via Digitalmars-d]

On Wednesday, 28 June 2017 at 12:17:36 UTC, Enamex wrote:
> Why do we need to name the result at all?
>
> Any conflicts with using
> `out(out > 0, "message")`

No conflict AFAICT. I personally don't like it, though.

> `out(return > 0, "message")`?

Yes, see [1]

> `out(someCond($), "message")`?

Overloading symbols with context dependent meaning is one more 
step into obfuscation.

> So using either `out` or `return` or `$` or whatever to always 
> refer to the return value of the function. Just something 
> that's already relevant and used instead of `__result`.

Well, `__result` is already implemented and usable, so I would 
argue it is thus relevant.

> R foo(Args...)(Args args) {
>     out(return > bar && ensured(return), "foo() fudged its 
> return");

Contracts inside function bodies should not be allowed imho.

[1] http://forum.dlang.org/post/oihbot$134s$1@digitalmars.com