manually call opUnary

[Rikki Cattermole via Digitalmars-d-learn]

On 4/11/2014 8:19 p.m., Algo wrote:
> Is it possible?
> As in
> {
>       int a;
>       a.opUnary!"++"();
> }
> no property 'opUnary' for type 'int'

For primitives it doesn't look like it.

To confirm this, we'll first figure out what TypeInfo is used for it:
pragma(msg, typeid(int).name);

/d133/f260.d(16): Error: no property 'name' for type 'object.TypeInfo'
/d133/f260.d(16):        while evaluating pragma(msg, (&typeid(int)).name)

So straight object.TypeInfo. Here is it in druntime:
https://github.com/D-Programming-Language/druntime/blob/master/src/object.di#L66

Because of this, it means its most definitely handled by the compiler 
itself.
But you can freely do this for classes:

import std.stdio;

class Foo {
	void opUnary(string op)() {
		writeln(op);
	}
}

void main() {
	Foo foo = new Foo;

	foo++;
	foo.opUnary!"--";
}

Outputs:
++
--