Deprecate implicit `int` to `bool` conversion for integer literals

[Michael V. Franklin]

On Tuesday, 14 November 2017 at 13:43:32 UTC, Michael V. Franklin 
wrote:

>>> An very similar problem exists for int and char overloads:
>>> 
>>> alias foo = (char c) => 1;
>>> alias foo = (int i) => 4;
>>> 
>>> enum int e = 7;
>>> static assert(foo(e) == 4); // fails
>>
>> Thanks. Addressing this should be part of the DIP as well. --
>
> It doesn't appear to be related to the implicit conversion of 
> integer literals to bool.  While Andrei's example is fixed by 
> by deprecating implicit conversion of integral literals to bool 
> (at least using this implementation: 
> https://github.com/dlang/dmd/pull/7310), Nick's example isn't.

Well, of course it's not related; it's a char not a bool.  But 
there does seem to be some systematic problems in D's implicit 
conversion rules.  I'll have to investigate this and perhaps I 
can address them both in one DIP.

Mike