Aliasing issue

[Lain]

Hi again,

I want to Alias "Game_CharacterBase.prototype.canPass", but doing so prevents the player from moving at all.

Original code:

Game_CharacterBase.prototype.canPass = function(x, y, d) {
    var x2 = $gameMap.roundXWithDirection(x, d);
    var y2 = $gameMap.roundYWithDirection(y, d);
    if (!$gameMap.isValid(x2, y2)) {
        return false;
    }
    if (this.isThrough() || this.isDebugThrough()) {
        return true;
    }
    if (!this.isMapPassable(x, y, d)) {
        return false;
    }
    if (this.isCollidedWithCharacters(x2, y2)) {
        return false;
    }
    return true;
};

Aliased version that doesn't work:

var alias_Game_CharacterBase_canPass = Game_CharacterBase.prototype.canPass;
Game_CharacterBase.prototype.canPass = function(x, y, d) {
    alias_Game_CharacterBase_canPass.call(this,x,y,d);
};

It seems to automatically return false, so the player can't move at all. The player can still turn around and everything but moving works.

I want to avoid overwriting. Any ideas?

 

[Galv]

You will see in the original function that it uses 'return' to return something when the function is run.
In your alias, you aren't returning anything.

Try putting return before your alias call

 

[Lain]

That works, thank you! But now I am a bit concerned about functions that return things only under certain conditions.

 

[Galv]

I am not sure what your concern is about that.

 

[Trihan]

That's how return values work, Lain. In your alias you're calling a function that returns a value, but then you're not doing anything with it. A program will only do something with a return value if you tell it to.

 

[mogwai]

If you return the alias function, it will handle all the conditions.

 

[Lain]

Ah I see, thanks. I was not sure, if I had to use return or not on functions that only return stuff under conditions.