BOOL in Systypes.h

[Erik Groenhuis]

Spoke too soon.

As Erik Groenhuis <e.groenhuis at xs4all.nl> wrote:

> Systypes.h in OSLibSupport does it's own definition of BOOL (and NULL):
> 
> ------8<------------
> #if !defined BOOL
>   #define BOOL bool
> #endif
> 
> #if !defined NULL
>   #define NULL ((void*)0)
> #endif
> ------8<------------
> 
> This is unwise, as there is a very good definition of BOOL in
> oslib/types.h, which takes into account various compilers.

oslib/types.h does not define BOOL. It defines BOOL_DEFINED, and if
needed does a

typedef osbool bool;

The reason I hit problems is because the !Dustbin example uses BOOL as
if it is a defined type:

====== main.h ======
void Main_SetIconFull( BOOL bTrue );
====================

while there is no definition in the headers, except for the one
mentioned above, and in oslib/macros.h, where it is defined as:

====== macros.h ========
/* ------------------------------------------------------------------------
 * Macro:         BOOL()
 *
 * Description:   Converts non-0 values to 1
 */

#define BOOL(c) ((c) != 0? TRUE: FALSE)
========================

This conflicts with Systypes.h *and* is unneccesary. Instead of the
BOOL(x) the programmer can simply write (!!x) or (TRUE && x), and the
compiler will convert from zero/nonzero to zero/-1.

So the chain goes like this:
In the !Dustbin example, main.h uses BOOL.
BOOL is #defined in Systypes.h as bool.
oslib/types.h ensures bool is typedef-ed.
(In my Norcroft C99 compiler, bool is typedef-ed in C:stdbool.h).

My remaining gripe is now with oslib/macros.h. The macro def there
prevents a succesful compilation of the !Dustbin example.

-- 
Erik Groenhuis http://www.xs4all.nl/~erikgrnh
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