Hi group,
When filling in my Windows(tm) structs, I use
NULL for object pointers and 0 for ints, floats etc.
I found out that this compiles:
int a=NULL;
float b=NULL;
etc.
Is that valid?
-X
48  12525 
Agent Mulder wrote: Hi group,
When filling in my Windows(tm) structs, I use
NULL for object pointers and 0 for ints, floats etc.
I found out that this compiles:
int a=NULL;
float b=NULL;
etc.
Is that valid?
NULL is almost certainly defined as
#define NULL 0
So why not? It's just substituted text.
"Dimitris Kamenopoulos" <dk*********@cs lab.ece.ntua.gr > wrote in message
news:bj******** ***@ulysses.noc .ntua.gr... Agent Mulder wrote:
Hi group,
When filling in my Windows(tm) structs, I use
NULL for object pointers and 0 for ints, floats etc.
I found out that this compiles:
int a=NULL;
float b=NULL;
etc.
Is that valid?
NULL is almost certainly defined as
#define NULL 0
So why not? It's just substituted text.
I think this illustrates what a waste of time NULL is. Its pretending to be
a special pointer value, but really it just zero. Don't pretend, use zero.
john
"Agent Mulder" <mb************ *******@home.nl > wrote in message news:bj******** **@news3.tilbu1 .nb.home.nl... Hi group,
When filling in my Windows(tm) structs, I use
NULL for object pointers and 0 for ints, floats etc.
I found out that this compiles:
int a=NULL;
float b=NULL;
etc.
It's valid in C++, but kind of silly. C++ requires NULL to be a macro
for an integer constant expression evaluating to zero.
Note however, that it's not a good idea in C. C allows (stupidly in my
opinion) the addition of a (void*) cast on the value 0. This won't allow
assignment to numeric types.
"John Harrison" <jo************ *@hotmail.com> wrote in message
news:bj******** ****@ID-196037.news.uni-berlin.de... > NULL is almost certainly defined as
#define NULL 0
So why not? It's just substituted text.
I think this illustrates what a waste of time NULL is. Its pretending to
be a special pointer value, but really it just zero. Don't pretend, use zero.
Yeah, this is one of those things that seems to obfuscate with no apparent
benefit. I remember seeing some code once where someone who was taught to
define constants for "Everything " got carried away.
#define ONE 1
God, can you imagine? One of the benefits of using a constant is that if a
value ever changes, it can be changed in one place, not many places. What
if the value actually did change?
> > > NULL is almost certainly defined as #define NULL 0
So why not? It's just substituted text.
I think this illustrates what a waste of time NULL is. Its pretending to
be a special pointer value, but really it just zero. Don't pretend, use
zero.
Yeah, this is one of those things that seems to obfuscate with no apparent
benefit. I remember seeing some code once where someone who was taught to
define constants for "Everything " got carried away.
#define ONE 1
God, can you imagine?
Yes I can, I know of someone who used macro's to turn a C compiler into a
(sort of) Pascal compiler. Unfortunately he was the only one who could make
sense out of his code. Macros are the ideal tool to obfuscate code, and some
people really do love this kind of thing.
--
Peter van Merkerk
peter.van.merke rk(at)dse.nl
Peter van Merkerk wrote:
[SNIP] #define ONE 1
God, can you imagine?
Yes I can, I know of someone who used macro's to turn a C compiler
into a (sort of) Pascal compiler. Unfortunately he was the only one
who could make sense out of his code. Macros are the ideal tool to
obfuscate code, and some people really do love this kind of thing.
Hehe. A college of mine turned C into Korn shell. His code was something
like this:
if (..) then
fi
It took me (not knowing UNIX at all at that time) half an hour just to learn
what he is doing by reading his obfuscation header.
--
WW aka Attila
"White Wolf" <wo***@freemail .hu> wrote in message news:bj******** **@phys-news1.kolumbus. fi... Peter van Merkerk wrote:
[SNIP] #define ONE 1
God, can you imagine?
Yes I can, I know of someone who used macro's to turn a C compiler
into a (sort of) Pascal compiler. Unfortunately he was the only one
who could make sense out of his code. Macros are the ideal tool to
obfuscate code, and some people really do love this kind of thing.
Hehe. A college of mine turned C into Korn shell. His code was something
like this:
if (..) then
fi
If you ever saw what the Bourne shell (and certain of Steve's other programs)
looked like. He spent a lot of time making C look like ALGOL or something.
>> #define ONE 1
God, can you imagine?
Yes I can, I know of someone who used macro's to turn a C compiler into a
(sort of) Pascal compiler. Unfortunately he was the only one who could make
sense out of his code. Macros are the ideal tool to obfuscate code, and
somepeople really do love this kind of thing.
Yes. It was the THE fun in assembler. Building
your own lego. In C++, #define is among the
more ugly features.
-X
John Harrison wrote: "Dimitris Kamenopoulos" <dk*********@cs lab.ece.ntua.gr > wrote in message
news:bj******** ***@ulysses.noc .ntua.gr...
Agent Mulder wrote:
Hi group,
When filling in my Windows(tm) structs, I use
NULL for object pointers and 0 for ints, floats etc.
I found out that this compiles:
int a=NULL;
float b=NULL;
etc.
Is that valid?
NULL is almost certainly defined as
#define NULL 0
So why not? It's just substituted text.
I think this illustrates what a waste of time NULL is. Its pretending to be
a special pointer value, but really it just zero. Don't pretend, use zero.
IMHO you are wrong. NULL is provided for readability and to express an
idea that is not representable by a number. We don't care what the
number is, what we care is if the pointer is labeled as invalid.
Macro definitions of constants is not just so that you can change the
definition in a single place, but also to convey ideas about the code.
john
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