Re: Alloc Struct
On Jul 8, 10:54 pm, Erik Wikstr=F6m <Erik-wikst...@telia.com> wrote:
On 2007-07-08 22:31, Brian C wrote:
I was going through various online C++ tutorials trying to possibly
pick up some things I do not know about already.
One had a question on it, along the lines of:
Q. Which of the following lines allocates a struct:
1. int *p=new int;
2. *p=1;
3. int *q=new int(2);
4. Range r=new Range(2,4);
I didn't finish this tutorial/quiz as I found some of the wording on
other questions a bit vague so I didn't get the answers.
I assume it is choice 4, but I never heard creating a new instance
"allocating a struct".
BTW, I know it looks like homework, but believe me, it isn't. I have=
n't
had homework to do in years.
It's quite bad language, first memory is allocated for the struct
(assuming Range is a struct), then the struct is created (instantiated)
on that memory address. In C++, unlike C, you don't generally just
allocate memory, usually you also create one or more objects in it.
And in C++, you don't generally have struct's. (Depending on
context, a "struct" is a class declared using the keyword
struct, or a POD struct. Or maybe just an agglomerate. In all
cases, it is a non-union class type, and one cannot know whether
it is a "struct" without seeing the definition.)
As you say, it's quite bad language.
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