if(arr) now a warning

[Martin Nowak via Digitalmars-d]

On 04/29/2015 09:15 PM, Jonathan M Davis wrote:
> Yeah, but I think that it's safe to say that std.allocator is not the
> normal case

std.allocator really isn't a general example.

I'm exclusively using if (ary.length) or if (!ary.empty) in my code to
avoid the problem.
Occasionally I'm using if (auto ary = func()), despite the fact that the
semantics are wrong, but it's nice and short and works as long a func
always returns null instead of empty slices.
But it's very fragile, hard to spot during debugging, and I already
spent too many hours on that.

So I'd expect any code analyzer to fault such usage and any D book to
teach people not to use arrays as boolean, at which point we'd be better
off to slowly remove it from the language.