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

[Enamex via Digitalmars-d]

On Wednesday, 28 June 2017 at 12:34:59 UTC, Moritz Maxeiner wrote:
> On Wednesday, 28 June 2017 at 12:17:36 UTC, Enamex wrote:
>> `out(return > 0, "message")`?
>
> Yes, see [1]

It has the already used `typeof(return)` going for it, though.

A big point against it IMO would be its moving further from 
`return`'s
signal that a function scope is exited at that line (instead it 
could
be a variable assignment which is meh (usage in a contract check 
is OK
since we're already outside the function)).

>> `out(someCond($), "message")`?
>
> Overloading symbols with context dependent meaning is one more 
> step into obfuscation.

True.

>> 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.

It's not used in the wild yet though :T

>> 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

I was going with the current 'Proposal' syntax in the DIP's 
document. There
a more recent proposal here?