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[This was posted by Alan Watson back in 1996, passing on a suggestion by Mark Brader. Dik Winter believes that the original idea was due to Karl Heuer.]

For this purpose, probably the best thing is some creative use of macros. (I wish I could remember who invented this little trick.) You can write the 16-bit binary number 1100110011110000 as
	B16( X X O O X X O O X X X X O O O O )
if you first define
 	#define X <<1)+1
 	#define O <<1)
 	/* the argument of B16 must be a total of 16 occurrences of
 	   one or the other of the above two macros, effectively
 	   expressing a number in binary */
 	#define B16(arg) (((((((((((((((((0 arg)
For visual purposes it may be even better to use _ as the name for the zero-bit, rather than O; but there's a loss of portability then, since the identifier _ is in the C implementation's name space and therefore may be used for some purpose in some implementations. Another good choice would be o, which suggests 0 without looking quite so much like it.

If you're using an unsigned type for the bitmap, as one normally should, then cast the 0 to that type inside the definition of the macro B16.


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