Hex floats

[Timon Gehr]

On 02/17/2012 10:45 AM, Don Clugston wrote:
> On 16/02/12 17:36, Timon Gehr wrote:
>> On 02/16/2012 05:06 PM, Don Clugston wrote:
>>> On 16/02/12 13:28, Stewart Gordon wrote:
>>>> On 16/02/2012 12:04, Don Clugston wrote:
>>>>> On 15/02/12 22:24, H. S. Teoh wrote:
>>>>>> What's the original rationale for requiring that hex float literals
>>>>>> must
>>>>>> always have an exponent? For example, 0xFFi obviously must be float,
>>>>>> not
>>>>>> integer, so why does the compiler (and the spec) require an exponent?
>>>>>
>>>>> The syntax comes from C99.
>>>>
>>>> Do you mean the syntax has just been copied straight from C99 without
>>>> any thought about making it more lenient?
>>>>
>>>> Stewart.
>>>
>>> Yes. There would need to be a good reason to do so.
>>>
>>> For the case in question, note that mathematically, imaginary integers
>>> are perfectly valid. Would an imaginary integer literal be an idouble, a
>>> ifloat, or an ireal? I don't think it could be any:
>>>
>>> foor(float x)
>>> foor(double x)
>>> fooi(ifloat x)
>>> fooi(idouble x)
>>>
>>> foor(7); //ambiguous, doesn't compile
>>> fooi(7i); // by symmetry, this shouldn't compile either
>>
>> static assert(is(typeof(7i)==idouble));
>
> Ooh, that's bad.
>

Indeed. But the implementation of complex and imaginary numbers is 
pretty much broken in the front-end anyway. For example, double and 
idouble are type combined to double iirc.