I've got a fairly complex D project (25+ modules) that has grown haphazardly over time. So it is not well designed. But I want to get the thing fully ported before refining the code. (that's called refactoring, I believe?)

Anyway, there is a new module called audio.d which which has all the sound functionality.

And in the (main.d) module is a code snippet like so

void main(string[] argv)
{
    // . . .
    auto blop = new AlurePlaySound("../bleep.wav");
    blop.play();
    // . . .
}

So all is well and good except I need to place the sound in another module (game.d) where
collisions are detected.

I tried:

module game;
import main;   // is this as ugly as I think it is?

if (collision[0])  // If collision make sound
    blop.play();


but this returns:  game.d(501): Error: undefined identifier 'blop'


So can someone tell me what various solutions to this problem or type of problems?  I presume there are quick and dirty solutions (like here) and more elegant solutions?

Would this type of problem fall under the domain of "scope".  Like in global scope. But I don't think D has such a concept.

Thanks.

On Thursday, 2 June 2016 at 00:37:58 UTC, WhatMeWorry wrote:
> I've got a fairly complex D project (25+ modules) that has grown haphazardly over time. So it is not well designed. But I want to get the thing fully ported before refining the code. (that's called refactoring, I believe?)
>
> Anyway, there is a new module called audio.d which which has all the sound functionality.
>
> And in the (main.d) module is a code snippet like so
>
> void main(string[] argv)
> {
>     // . . .
>     auto blop = new AlurePlaySound("../bleep.wav");
>     blop.play();
>     // . . .
> }
>
> So all is well and good except I need to place the sound in another module (game.d) where
> collisions are detected.
>
> I tried:
>
> module game;
> import main;   // is this as ugly as I think it is?
>
> if (collision[0])  // If collision make sound
>     blop.play();
>
>
> but this returns:  game.d(501): Error: undefined identifier 'blop'
>
>
> So can someone tell me what various solutions to this problem or type of problems?  I presume there are quick and dirty solutions (like here) and more elegant solutions?
>
> Would this type of problem fall under the domain of "scope".  Like in global scope. But I don't think D has such a concept.
>
> Thanks.

Since blop is being declared inside your main() function, it isn't visible to other modules or functions. You're right that the issue is a problem of "scope".

Importing your main module will work, but you must declare your as a global variable outside the main() function.

i.e.

----------------------

module main;

AlurePlaySound blop;

void main()
{
   //etc...

   blop = new AlurePlaySound("../beep.wav");

   //etc...
}

----------------------

module game;

import main;

void collision()
{
    blop.play(); //or whatever
}

If your game loop is running in a separate thread, then I think you'll want to use:

__gshared AlurePlaySound blop;

for the declaration, since variables are thread-local by default.

Using global variables is generally frowned upon for production code because you can never be sure which functions are modifying it. But for a quick hack, it works! A better option might be to make a third module with a class containing all your audio objects, initialize it in main(), and then pass it to your main game loop.

-Jon