In article <rfgCLJF7v.1Io@netcom.com> rfg@netcom.com (Ronald F.
Guilmette) wrote:

N>>Yesterday, in a design meeting that got a little too deep into
N>>implementation, someone asked if a const data member was treated like
N>a >static data member by the compiler.
N>>
N>>It would seem that the compiler could know that since the data member
N>could >not be changed it is not necessary to allocate space for it in
N>every >instantiation.

Just because a member is defined as const does NOT mean that its value
will be the same for every instantiation.

class A {
   const int i;
   int j;
public: A( int ii, int jj ) : i(ii), j(jj) {};
};
A a1(1,2);
A a2(3,4);

a1 and a2 have different values of i, but neither of them may be
changed.

If I am wrong, will someone please correct me, gently!

Martin Horton - Fort Worth, Texas 02/22/94 08:11
Internet:
Personal:  Martin.Horton@Chrysalis.org
Business:  Z5319@aa1profs.ibmmail.com
Fidonet    Martin Horton @ 1:124/4214

martin.horton@chrysalis.org writes:

>Just because a member is defined as const does NOT mean that its value
>will be the same for every instantiation.

100%, and so it should be.  BUT, what SHOULD be usable is:


class foo {
public:
        static const int i=1234;
};


But alas, this is not allowed.  Instead we resort to:


class foo {
public:
 enum { i=1234, j=4128 };
};


But this doesn't even extend as far as:


class foo {
public:
        enum { x=1.234, y=4.128 };
};


--
Warwick