I stand corrected and feel somewhat enlightened...but only somewhat, since I don't quite get all your math speak. Oh well, it makes sense. Do you happen to have a link to the C++ thread? I'd love to read it, but a search for "predetermined integers" gave me 2 irrelevant threads, and I don't quite feel like sifting through laserlight's and Elysia's combined 30,000+ posts. Thanks.
That does not matter as the operations are equivalent (and the equivalence is explicitly stated in C99, though in the (0 == c) form). That is b1nd3r's point, so there is no point nitpicking, unless you want to insist that *p is not "equal" (as in equivalent) to p[0], since they are two different operations with the same result in the end.Originally Posted by Elysia
Heheh, I don't have the link handy either, but...
It does say what kind of non-zero value: the result is of the type int with a value of 1.
Look up a C++ Reference and learn How To Ask Questions The Smart Way
Yeah that's what I was trying to say as well, I guess you just have a gift of putting thoughts into words better, which would explain your gazillion posts
.
1. Get rid of gets(). Never ever ever use it again. Replace it with fgets() and use that instead.
2. Get rid of void main and replace it with int main(void) and return 0 at the end of the function.
3. Get rid of conio.h and other antiquated DOS crap headers.
4. Don't cast the return value of malloc, even if you always always always make sure that stdlib.h is included.
Anduril462,
The link you requested: Inputting a dynamic, mutable character array with spaces
The discussion was about how silly it is to use an integer type for a pointer value (I think it escalated to an evil eventually) ...a funny symmetry to this discussion -- I thought at the time.
Best Regards,
New Ink -- Henry
Kept the text books....
Went interdisciplinary after college....
Still looking for a real job since 2005....
During the interim, I may be reached at ELance, vWorker, FreeLancer, oDesk and WyzAnt.
K&R's C, Chapter 2, Section 6.
"The unary negation operator ! converts a non-zero operand into 0, and a zero operand into 1. A common use of ! is in constructions like
rather thanCode:if (!valid)
It is hard to generalize which form is better."Code:if (valid == 0)
(Kernighan and Ritchie 42).
It reads as "not", but can also mean "empty." More closely, it can read, "opposite." [Difference between zero and empty; we'll spare you the semantics as you've probably already thought about it some.]
Increments built up from zero are easy to imagine; but, sometimes the shorter path is to understanding what a condition is not; then, from there, building out the response. Sometimes very handy for those moments when you're going back and forth over a variable used as a trigger, without wanting to completely reset everything to the concept of "zero"; instead, you can employ the "!" as part of a procedure for checking for a change in state or changing a state. From there, continue programming.
For this reason, it can be handy to invert the presence of electricity into its absence, or absence into presence. So, there is an operator for that concept, it's the "!".
True into false; false into true. Good luck.
Last edited by agxphoto; 11-25-2010 at 09:42 AM.
Why do people keep insisting on quoting K&R which is like 30-something years old now? If you're going to quote something, quote the C99 standard. Which, by the way, has this to say:
"The result of the logical negation operator ! is 0 if the value of its operand compares
unequal to 0, 1 if the value of its operand compares equal to 0. The result has type int.
The expression !E is equivalent to (0==E)."
Last edited by itsme86; 11-25-2010 at 10:30 AM.
If you understand what you're doing, you're not learning anything.
Well, if I didn't quote K&R's C, then you might have mistaken all of those great ideas for my own!
Last edited by agxphoto; 11-25-2010 at 11:48 AM.
