Adding Unicode operators to D [use cases]

[bearophile]

Sergey Gromov:
> I'd use dot "⋅" and cross "×" products for 3D, union "∪" and
> intersection "∩", subset "⊂" and superset "⊃" and their negative forms.
>  I don't think I'd use anything else.

I just want to note that the whole thread is almost unreadable on the digitalmars.com/webnews/, because it doesn't digest unicode chars at all. So adding unicode to D will give problems to show code.

Unrelated to the unicode, but related on those opSubset, opSuperset, etc:
while implementing a set() class with the same API of the Python sets, I have seen there are the following operators/methods too:

issubset(other) 
set <= other 
Test whether every element in the set is in other.

set < other 
Test whether the set is a true subset of other, that is, set <= other and set != other.

issuperset(other) 
set >= other 
Test whether every element in other is in the set.

set > other 
Test whether the set is a true superset of other, that is, set >= other and set != other.

A full opCmp can't be defined on sets, so I think in D1 we can't overload <= >= among sets... I think this is a problem has to be solved in D2, because sets are important enough.

Bye,
bearophile