Wasn't it [GDS|Entropy] who wrote:
>Hello,
>
>A little stuck here... evidently povray does not support any type of
>Return() function, and I am not familiar enough with sdl yet to figure this
>out any other way.
>This little macro does what it says, but not in this form.
>
>#macro isEvenOrOdd(integer)
> #if(mod(integer,2) = 0)
>  #local isEven = 1;
> #else
>  #local isOdd = 1;
> #end
>#end
 >
>There HAS to be some way to pass variables from a macro...right? :-\

You're confusing the concept of MACRO with the concept of FUNCTION.

The entire contents of a macro are "returned", so you can write:


#macro isEven(integer)
  #if(mod(integer,2) = 0)
   #local even = 1;
  #else
   #local even = 0;
  #end
  (even)
#end

#if (isEven(3))
   #debug "3 is even\n"
#else
   #debug "3 is odd\n"
#end


Or
#macro isOdd(integer)
  (mod(integer,2))
#end

#if (isOdd(3))
   #debug "3 is odd\n"
#else
   #debug "3 is even\n"
#end


Don't get confused into thinking that those macros get evaluated and 
then return integer values. They "return" chunks of SDL code like
   #if(mod(3,2) = 0) #local even=1; #else #local even = 0; #end (even)
And what happens is that
   #if (isEven(3))
effectively becomes
   #if (#if(mod(3,2) = 0) #local even=1; #else #local even = 0; #end 
(even))
and THEN gets evaluated.

-- 
Mike Williams
Gentleman of Leisure

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