:? in templates

[retard]

Wed, 18 Nov 2009 03:31:11 -0800, Bill Baxter wrote:

> On Wed, Nov 18, 2009 at 3:16 AM, retard <re at tard.com.invalid> wrote:
>> Wed, 18 Nov 2009 03:10:57 -0800, Bill Baxter wrote:
>>
>>> Didn't this used to work?
>>>
>>> template factorial(int i) {
>>>     enum factorial = (i==0) ? 1 : i*factorial!(i-1);
>>> }
>>>
>>> With DMD 2.036 I'm getting:
>>>   Error: template instance factorial!(-495) recursive expansion
>>>
>>> Seems like it expands both branches regardless of the condition. And
>>> seems to me like it shouldn't.
>>
>> There's probably a confusion here. It evaluates lazily the value of
>> factorial!(), but its type (which happens to be infinitely recursive
>> must be evaluated eagerly in order to infer the type of the ternary op.
> 
> That makes sense.  I guess the ?: op is defined to do that in all cases.
>  Might be nice though if it didn't do that in cases where the condition
> was statically known.

so

 int foo = (1==1) ? 6 : "haha";

would work, too? I think it would still need to check that the types of 
both branches match.