From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Robert P. J. Day" <rpjday@mindspring.com>
Subject: using compile-time "assertions"
Date: Sun, 5 Jun 2005 16:36:34 -0400 (EDT)
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  another question (one of undoubtedly many) regarding the code i
inherited.  in this code, there is liberal use of the following macro:

#define INVARIANT(e) \
  do { \
    struct whatever { char static_assertion[(e) ? 1 : -1]; }; \
    } while (0)

which i recognize as a *compile-time* assertion/invariant.  is this a
common construct?  just curious.  or is there a more popular variant
of this sort of thing?  i recognize its value but, geez, there's
hundreds of these things in the code. :-P

rday