Jonathan M Davis
jmdavisProg at gmx.com
Tue Jan 3 15:31:46 PST 2012
On Tuesday, January 03, 2012 17:41:12 simendsjo wrote:
> I guess this is as designed, but I'll ask anyway.
> http://dlang.org/operatoroverloading.html#Cast says an expression is
> rewritten to opCast "whenever a bool result is expected".
> This is true for
> if(e) somethingElse
> and e && somethingElse
> , but not for other parts.
> assert(cast(bool)e == true); // explicit cast works
> assert(e == true); // Error: incompatible types for ((s) == (false)):
> 'S' and 'bool'
> is(typeof(e) : bool); // false
Yeah. It's the same for built-in types. Take arrays and pointers for example.
They don't implicitly convert to bool, but when you use them in a condition,
they implicitly convert to bool (true if they're non-null, false if they're
null). If you want implicit conversion in general, then you need to use alias
- Jonathan M Davis
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