🚀 go-pugleaf

In article <2571@watcgl.waterloo.edu>, kdmoen@watcgl.waterloo.edu (Doug Moen) writes:
} Although I haven't seen this exact trick used in any Mac C environment
} so far, it *is* possible to define Rect so that you can use the
} syntax described in Inside Macintosh for accessing its fields:
} 
} typedef struct {
} 	Point topLeft;
} 	Point botRight;
} } Rect;
} 
} #define top	topLeft.v
} #define left	topLeft.h
} #define bottom	botRight.v
} #define right	botRight.h
} 
} Note that LightSpeed C defines top,left,bottom and right as fields
} and topLeft,botRight as macros, while the above implementation does
} the reverse, *and* gives you a cleaner syntax.
} -- 
} Doug Moen
} University of Waterloo Computer Graphics Lab
} UUCP:     {ihnp4,watmath}!watcgl!kdmoen
} INTERNET: kdmoen@cgl.waterloo.edu

     The problem here is that you can no longer use variables with the names
top, left, bottom or right.  One of the old Megamax C's did something like
this as I recall.  (It wasn't necessarily this example.)  I wrote a program
in which I used a variable called "top" (using this as an example.)  We all
know how good most C compilers are at explaining the problem...
     I spent quite some time trying to figure out why

	int top;

     gave a "Syntax Error."

     Variables with the names top, left, bottom and right are much more common
in C programs than variables named topLeft, botRight, so that's why the macros
are done in a non-intuitive manner.

Brian H. Powell
		UUCP:	...!uunet!ut-sally!brian
		ARPA:	brian@sally.UTEXAS.EDU

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