Super-dee-duper D features

[Andrei Alexandrescu (See Website For Email)]

Bill Baxter wrote:
> Andrei Alexandrescu (See Website For Email) wrote:
> 
> 
>> I'm actually mildly surprised. Lately there was some talk around here 
>> about supporting the day-to-day programmers and so on. I find looping 
>> a very day-to-day thing, and looping over 2+ things at least a 
>> few-days-to-few-days thing. There is a need for parallel iteration, if 
>> nothing else shown by the existence of a library that addresses 
>> exactly that - to the extent possible in a library that's not in the 
>> position to control syntax, scoping, and visibility. I was sure people 
>> will be on this one like white on rice. But Bjarne Stroustrup was 
>> right: nobody knows what most programmers do :o).
> 
> Python and Ruby are hardly considered to be obtuse languages, or 
> unfriendly to Joe coder, but both get by just fine without special case 
> syntax for iterating over multiple collections, or for iterating in 
> reverse.
>    for x,y izip(foo,bar):
>        do stuff
> 
>    for x reversed(foo):
>        do stuff
> 
>    for x,y izip(reversed(foo),bar):
>        do that with your proposal!

foreach (x ; reverse_view(foo)) (y ; bar)
   probably I could!

> That said, I understand that Python and Ruby have a little more freedom 
> to pile up the abstractions because both of them are so friggin slow 
> that a few more layers won't hurt anything.  D can't be quite so 
> cavalier about tossing performance for elegance.

Yah. Costly abstractions are a dime a dozen.

> Still, I'm remain unconvinced that D can't have both performance and 
> elegance.

Macros will get us closer to that.


Andrei