Re: Is the concept of class optional in C++?
On Apr 7, 5:29 pm, jacob navia <ja...@nospam.com> wrote:
We were discussing this point in comp.lang.c
1) Some people say that templates and classes are "optional" in C++.
Define "optional". The following doesn't use either, and is
certainly a legal C++ program:
#include <cstdio>
int
main()
{
std::printf( "Hello, world!\n" ) ;
return 0 ;
}
In practice, I don't think you can write much C++ without
classes, since C++ doesn't have structures. (The keyword struct
defines a class.) But since a class with only public data
members is indistinguishable from a C struct, who cares.
Templates, of course, are completely optional, and I've written
a lot of C++ code which doesn't use them. (Don't forget that
they are a relatively late addition to the language.)
Practically, of course, the question is: why would you want to?
I spend something like ten years programming in C, defining a
struct and a set of functions to manipulate it, and crossing my
fingers that no one accessed it other than through those
functions. At the very least, you want the access control of
classes.
Beyond that, there are certain (very common) cases where
inheritance, templates or operator overloading make life
significantly simpler, and the resulting code significantly more
robust. Why not use them then?
[...]
But I think that is wrong. One of the central concepts in C++
is the concept of class and inheritance,
Historically, and even today, the essential thing that C++ adds
to C is access control. All the rest are nice added features,
which help solve certain problems; access control is
fundamental.
--
James Kanze (GABI Software) email:james.kanze@gmail.com
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