code understanding help

[Devon H. O'Dell]

On Sun, Apr 03, 2005 at 07:09:00PM +0200, Erik Wikström wrote:
> 
> "Terry Tree" <terry.tree at xxxxxxxxx> wrote in message
> news:60e7ec9505040309364929a941 at xxxxxxxxxxxxxxxxx
> > I'm trying to go through a book on programming in C and I'm having
> > problem understanding the second example in the book.
> >
> > $cat 2.c
> >
> > #define PRINTX printf("%d\n", x);
> >
> > int
> > main(int argc, char *argv[])
> > {
> >     int x = 2, y, z;
> >
> >     x *= 3 + 2; PRINTX;
> >     x *= y = z = 4; PRINTX; // the output makes no sense
> >     x = y == z; PRINTX;
> >     x == (y = z); PRINTX;
> > }
> >
> > Looking at line x *= y = z = 4; from my point of view the output
> > should be 8 but it is 40.
> 
> Allow me to post another question, I have no experience with C but the third
> line looks fishy to me. Would in not be interpreted as x =(y==z), which
> should be true, but x is an int. I know of inexplicit casting from int to
> bool but never heard of bool to int. Am I missing something?
> 
> --
> Erik Wikström

C has no bool type. False evaluates to 0 and true evaluates to 1
is is shown from this code. I really don't like this example,
though.

--Devon
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