opPow, opDollar

[Don]

Walter Bright wrote:
> Don wrote:
>> A little while ago I said I'd create a patch for ^^ as an 
>> exponentiation. A couple of people had requested that I make a post to 
>> the ng so they'd know when it happens. Here it is.
>>
>> This is opPow(),  x ^^ y
>>
>> http://d.puremagic.com/issues/show_bug.cgi?id=3481
> 
> I don't understand the rationale for an exponentiation operator. It 
> isn't optimization, because pow() could become an intrinsic that the 
> compiler knows about. pow() is well known, ^^ isn't. (Fortran uses **)

It's primarily about syntax sugar: pow() is so ugly. In practice, the 
most important case is squaring, which is an extremely common operation. 
pow(xxx,2) is horribly ugly for something so fundamental. It's so ugly 
that noone uses it: you always change it to xxx * xxx. But then, xxx 
gets evaluated twice.

Yes, ^^ hasn't been used for exponentiation before. Fortran used ** 
because it had such a limited character set, but it's not really a 
natural choice; the more mathematically-oriented languages use ^. 
Obviously C-family languages don't have that possibility.