DIP80: phobos additions

[Wyatt via Digitalmars-d]

On Wednesday, 17 June 2015 at 09:28:00 UTC, Tofu Ninja wrote:
>
> I actually thought about it more, and D does have a bunch of 
> binary operators that no ones uses. You can make all sorts of 
> weird operators like +*, *~, +++, ---, *--, /++, ~~, ~-, -~,
> >>>--, &++, ^^+, in++, |-, %~, ect...
>
> void main(string[] args){
> 	test a;
> 	test b;
> 	a +* b;
> }
> struct test{
> 	private struct testAlpha{
> 		test payload;
> 	}
> 	testAlpha opUnary(string s : "*")(){
> 		return testAlpha(this);
> 	}
> 	void opBinary(string op : "+")(test rhs){
> 		writeln("+");
> 	}
> 	void opBinary(string op : "+")(testAlpha rhs){
> 		writeln("+*");
> 	}
> }

Oh right, meant to respond to this.  I'll admit it took me a few 
to really get why that works-- it's fairly clever and moderately 
terrifying.  (I showed it to a friend and he opined it may 
violate the grammar.)

But playing with it a bit...well, it's very cumbersome having to 
do these overload gymnastics.  It eats away at your opUnary space 
because of the need for private proxy types, and each one needs 
an opBinary defined to support  it explicitly.  It also means you 
can't make overloads for mismatched types or builtin types (at 
least, I couldn't figure out how in the few minutes I spent 
poking it over lunch).

-Wyatt