Re: Macros


Peter "Shaggy" Haywood wrote:
Groovy hepcat Walter Roberson was jivin' on Tue, 28 Nov 2006 07:57:39
+0000 (UTC) in comp.lang.c.
Re: Macros's a cool scene! Dig it!

In article <1164698162.284936.137360@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
Harry <gehariprasath@xxxxxxxxx> wrote:

I have a piece of code as

# define prod(a,b)=a*b
main()
{
int x=2;
int y=3;
printf("%d",prod(x+2,y-10));
}

will the macro be evaluated as (2+2)*(3-10)=4* -7 =-28.

No, each dummy argument will be *textually* dropped into place exactly
as specified. Thus, your line would expand to

printf("%d",x+2*y-10);

No, it would expand to this:

printf("%d",=x+2*y-10);

which is a syntax error.

- don't use = in the macro definition

Exactly.

--

Dig the even newer still, yet more improved, sig!

http://alphalink.com.au/~phaywood/
"Ain't I'm a dog?" - Ronny Self, Ain't I'm a Dog, written by G. Sherry & W. Walker.
I know it's not "technically correct" English; but since when was rock & roll "technically correct"?



Sorry guys,that = is not present in the maro expansion.It was my
mistake & thanks for clearing the doubt.

.

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