C++ use of bool

[Daniel Ellis]

Tony van der Hoff writes:
 > On Fri, 5 May 2000, at 16:06:10, David Bryan <D.J.Bryan at cranfield.ac.uk>
 > wrote on the subject "C++ use of bool":
 > 
 > >In message <sKii6NAb9oE5EwYI at mk-net.demon.co.uk>
 > >          Tony van der Hoff <OSLib at mk-net.demon.co.uk> wrote:
 > >
 > >> On Thu, 4 May 2000, at 17:50:51, David Bryan <D.J.Bryan at cranfield.ac.uk>
 > >> wrote on the subject "C++ use of bool":
 > >> 
 > >
 > >As it turns out, g++ hasn't always had |bool| as a keyword.  
 > 
 > My fledgling types.h now contains this:
 > 
 > --------------------------------------------------------
 > 
 > /* C99 defines bool as a keyword */
 > #if !defined BOOL_DEFINED && defined ( __STDC_VERSION__ )
 >   #if __STDC_VERSION__ >= 199901L
 >     #define BOOL_DEFINED
 >   #endif
 > #endif
 > 
 > /* GNU C++ defines bool as a keyword at V2.7 */
 > #if !defined BOOL_DEFINED && defined __GNUG__
 >   #if __GNUG__ > 2 || ( __GNUG__ == 2 && __GNUG_MINOR__ >= 7 )
 >     #define BOOL_DEFINED
 >   #endif
 > #endif
 > 
 > /* C++ (1998) defines bool as a keyword, 
 > ** but many implementations included it earlier 
 > */
 > #if !defined( BOOL_DEFINED ) && defined __cplusplus 
 >   /* CFront defines |__cplusplus| but not |bool| */
 >   if !defined __CC_NORCROFT
 >     #define BOOL_DEFINED
 >   #endif
 > #endif
 > 
 > #if !defined( BOOL_DEFINED )
 >    typedef osbool bool;
 > #endif
 > 
 > --------------------------------------------------------
 > 
 > Does anyone want to comment/criticise? Are there any other little twists
 > that I ought to know about before committing to this?

Shouldn't # be the first character on the line?  I've usually seen
indented preprocessor statements as:

#if THIS
/* only do is THIS */
#  if THAT
/* only do if THIS and THAT */
#  endif
#endif

Also, you've missed out a # on 'if !defined __CC_NORCROFT'

cheers,

-- 
Dan Ellis
Software Engineer
Climate Physics Group
Mullard Space Science Laboratory