Irritating shortcoming with modules and externs

[Mike Parker]

Jarrett Billingsley wrote:
> 
>> How about moving to a delegate model instead of a direct global symbol
>> model?  It's much more obvious, imho.
> 
> That's probably what I'll end up doing, although the function that I wanted 
> to do this with was main (so basically I could "intercept" the call to main 
> in my library, and call the user-defined "LibMain" or something to that 
> effect).  Of course, seeing that D is an OOP language, I might as well make 
> some kind of context class that wraps the entire program, ending you up with 
> something like:
> 
> abstract class Context
> {
> ...
> }
> 
> class MyContext : Context
> {
>     // override all those stubbed-out methods
> }
> 
> void main(char[][] args)
> {
>     MyContext c = new MyContext();
>     c.main(args);
> } 
> 
> 

How about this:

##########################################
// main.d
module main;

abstract class Context
{
public:
	abstract void run(char[][] args);
	
protected:
	this()
	{
		theContext = this;
	}
}

private Context theContext;

void main(char[][] args)
{
	theContext.run(args);
}

===========================================

// mygame.d
module mygame;

import main;

class MyContext : Context
{
public:
	override void run(char[][] args)
	{
		// blah
	}	
}

static this()
{
	new MyContext();
}
#######################################

I did something similar with a GameTask system I was working on. Works 
like a charm.