Matrix-type-friendly syntax and more

[Christophe]

bearophile , dans le message (digitalmars.D:146534), a écrit :
> Robert Jacques:
> 
>>[... several things]
>> Seventh, Matlab, NumPy, Octave, BLAS, etc. all support striding.
> 
> OK, a nice striding syntax for user defined types will be a good thing to have in D2.
> 
> I have suggested the x..y:y syntax. Is this usable? Is this going to cause problems?
> 
> Bye,
> bearophile

: is already used for labels. If slice types are allowed, this can 
cause trouble:

auto a = 0 .. 10; // a slice!(int, int) type.
a : 2; //  is it a label or a stride ?

Of course, the example here is obvious, but maybe in real code this can 
cause trouble.

stride(x..y, z) works just as good, and does not let people think it is 
a very efficient langage builtin.

The langage just have to allow to define iota-like types with ..

Then a[x..y] becomes an opIndex() like Kenji suggested, and slices can 
be used anywhere, like in :

multidimArray.columns(1..5);