Null references redux

[Jari-Matti Mäkelä]

Jeremie Pelletier wrote:

> Jari-Matti Mäkelä wrote:
>> Jeremie Pelletier wrote:
>> 
>>> Nick Sabalausky wrote:
>>>> union A {
>>>> int foo;
>>>> float bar;
>>>> }
>>>>
>>> Yet it's the only way I know of to do bitwise logic on floating points
>>> in D to extract the exponent, sign and mantissa for example.
>> 
>> You could add built-in methods for those operations to the float type:
>> 
>> float bar;
>> 
>> boolean s = bar.sign;
>> ...
> 
> That would be so inefficient in some cases, you don't always want to
> shift the data like bar.sign implies.

It depends on the boolean representation. I see no reason why a built-in 
feature should be slower than some bitwise logic operation in user code. 
After all, the set of operations the language provides for the user is a 
subset of all possible operations the language implementation can do.