Re: Fw: Re: [AD] messy allegro 5.0 stuff

[Hein Zelle <hein@xxxxxxxxxx>]

Sven Sandberg wrote:

> Yes, and this seems much cleaner than having to mask out the value, but
> how should it be done? Probably it would have to be something like
> 
>    void al_read_key(int *unicode, int *scancode);
> or
>    int al_read_key(int *scancode);

I personally dislike parameter lists like the above where you have
to provide 2 storage variables for return values, when you normally 
will be using only 1 at a time. Is it not possible to do something
like the following? (forget name clashes for a minute)

struct AL_KEY
{
    int unicode;
    int scancode;
};

struct AL_KEY al_read_key()
{
    struct AL_KEY k;

    /* fill in values */

    return k;
}

If you insist that passing a struct over the stack is ugly (which it
is, I guess, but with 2 integers I don't think it's _that_ bad) we
could always go for

void al_read_key(AL_KEY *);

or even

int al_read_key(AL_KEY *);

where the latter can return error values if required. I personally
prefer the first option (returning a struct) but passing a struct as
argument will do as well. IMHO, this makes it easier to use the
function as you only need to define one local variable. Returning a
struct also make the following possible:

if (al_read_key().scancode == KEY_BLADIEBLA)
{
    ...
}

Hein Zelle

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 Hein Zelle                     hein@xxxxxxxxxx
	                        http://www.icce.rug.nl/~hein
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