delegates, functions, and literals confusion

[Mike Parker]

On Thursday, 4 July 2013 at 13:23:23 UTC, CJS wrote:
> Thanks for the detailed answer!
>
> Just to clarify: So if f is an inner function then &f will be a 
> delegate even if it doesn't reference anything in the 
> environment in which it was defined? (i.e. even if it could 
> have been typed as a function?)

That is correct. Unless the inner function is static. I had 
actually forgotten about this until I just looked it up in the 
docs[1]. Taking the address of a static inner function will give 
you a function pointer rather than a delegate.

void foo() {
    static int f() { return 10; }
    int g() { return 20; }

    iTakeAFuncPtr( &f );
    iTakeADelegate( &g );
}

In which case you can modify static local variables:

import std.stdio;
void foo( int function( int ) fp ) {
     writeln( fp( 5 ));
}

void main() {
     static int k = 10;

     static int mult( int i ) { return i*10; }
     foo( &mult );
}

[1] http://dlang.org/function.html