Re: Ambiguities in VRML-Syntax

Richard Rabbat (ricky@ceci.mit.edu)
Sat, 02 Dec 1995 03:58:47 -0500

Mitra wrote:
>
> > > * SFBool according to ANSI-C: SFBools should also be TRUE if any value
> > > unequal 0 is detected.
> > No - TRUE is 1 FALSE is 0, any other value should be a syntax error
>
> I think ONLY TRUE/FALSE should be allowed for SFBools.
>
> That's a good idea, no numbers at all.
>Actually TRUE and FALSE do not really exist but they are something like:
#define TRUE 1
#define FALSE 0
so it would be better to leave the 0's and 1's which are things a programmer
would expect.
Together with that, being able to manipulate booleans as integers is such a
powerful tool. Not allowing 0 and 1 means going into an endless series of
pseudocode instructions like:

if (boolean variable = TRUE )
then ( set the whatever variable to 2
else ( set the whatever variable to 0)

which is much clumsier than saying:
whatever variable = 2 * boolean variable;

-- 
Richard Rabbat, Computer and Communications Engineer
Center for Educational Computing Initiatives
Massachusetts Institute of Technology


Email: ricky@ceci.mit.edu, rickie@mit.edu
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