bearophile wrote:
Andrei Alexandrescu:
* Encode operators by compile-time strings. For example, instead of
the plethora of opAdd, opMul, ..., we'd have this:
T opBinary(string op)(T rhs) { ... }
The string is "+", "*", etc.
Can you show an example of defining an operator, like a minus, with
that?
struct BigInt {
BigInt opBinary(string op)(BigInt rhs) if (op == "-") {
...
}
}
In my set data structure I'd like to define "<=" among two sets as
"is subset". Can that design allow me to overload just <= and >= ?
(opCmp is not enough here).
It could if we decide to deprecate opCmp. I happen to like it; if you
define a <= b for inclusion, people will think it's natural to also
allow a < b for strict inclusion. But that's up for debate.
I'm not sure what the best way is. Classes have opEquals and opCmp so
the question is - do we want structs to be somewhat compatible with
classes or not? My personal favorite choice would be to go full bore
with compile-time strings.
Andrei
