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In article <4jq60l$6pp@symiserver2.symantec.com> thoff@symantec.com
(Torsten Hoff) writes:

|> In article <4jgpqa$t09@nntp.interaccess.com>,
|>    brianmcg@interaccess.com (Brian V. McGroarty) wrote:
|> >Is this legal?  Borland and Microsoft compilers will accept the following:
|> >
|> >class AnyClass
|> >{
|> >    const int constInt;
|> >}
|> >
|> >The Borland compiler complains about the uninitialized constant, whereas
|> >the Microsoft compiler does not.  If a constructor is present, both will
|> >complain that the constant isn't initialized in the constructor, however
|> >neither will allow you to assign a value in the constructor by simply
|> >specifying "constInt= some value".  I have also attempted to initialize in
|> >a global variable "int AnyClass::constInt",  to determine whether static
|> >somehow became implicit -- still no go.  If this is legal, how is the value
|> >initialized?
|> [Snip]

|> That's perfectly legal.

|> However, you can't initialize the const member in the class
|> declaration, since you haven't instantiated an object of the class in
|> question which could receive the value. Furthermore, it would prevent
|> you from assigning different values to constInt in different instances
|> of the class, which in most cases is not what you want, either.

|> If you *really* want compile-time initialized constants, and can live
|> with something that has essentially the same properties as an integer,
|> use class-scope enums. If you need several compile-time constants with
|> the same value, you can use multiple untagged enums:

|> class AnyClass
|> {
|>     enum {FOO = 1, BAR = 1}; // multiple enums with same value; doesn't work!

Why not?  It is allowed by the standard, and works on all of the
compilers I've used.

|>     enum {FOO = 1};          // OK
|>     enum {BAR = 1};          // OK
|> }

The (minor) problem with this solution is that the type of the constant
may not be what you want.  This is probably only a problem when function
overloading is present, or templates.

The draft standard allows an initialization of a *static* const in the
class definition, e.g.:

    class X
    {
        static size_t const     mySize = 1024 ;
    } ;

This is a relatively new feature, however, and may not be supported by
your compiler.

	[Rest of correct answer deleted...]
-- 
James Kanze         Tel.: (+33) 88 14 49 00        email: kanze@gabi-soft.fr
GABI Software, Sarl., 8 rue des Francs-Bourgeois, F-67000 Strasbourg, France
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