> Why are so many macros written as: do { ... } while (0) rather than
> as simply { ... } ?
So that
if (condition)
MACRO();
else
foo;
works properly. There are other corner cases. Technically speaking, a
{}-macro expands to a BLOCK while the do{}while(0) expands to a STATEMENT.
The grammar for the C language treats these differently, and we usually
expect a macro to be a statement, not a block.
--Scott
@ @
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C. Scott Ananian: cananian@lcs.mit.edu / Declare the Truth boldly and
Laboratory for Computer Science/Crypto / without hindrance.
Massachusetts Institute of Technology /META-PARRESIAS AKOLUTOS:Acts 28:31
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