Re: Which is faster?

pete said:

<snip>

p += 1; /* a statement */

Right.

(p += 1) /* an expression */

Right.

'p += 1' /* not a c construct */

Er, wrong.

3.1.3.4 (C89): "An integer character constant is a sequence of one or more
multibyte characters enclosed in single-quotes, as in 'x' or 'ab'."

6.4.4.4(2) (C99): "An integer character constant is a sequence of one or
more multibyte characters enclosed in single-quotes, as in 'x'."

The difference between the above two quotes led me to poke around further
in C99:

6.4.4.4(10): "The value of an integer character constant containing more
than one character (e.g., 'ab'), or containing a character or escape
sequence that does not map to a single-byte execution character, is
implementation-defined."

Thus, 'p += 1' /is/ a C construct, albeit not a terribly useful one.

--
Richard Heathfield <http://www.cpax.org.uk>
Email: -http://www. +rjh@
Google users: <http://www.cpax.org.uk/prg/writings/googly.php>
"Usenet is a strange place" - dmr 29 July 1999
.

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