From: "Steve Ball" <steve AT effectivejava DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: const class& as a parameter.
Date: Mon, 12 Jul 1999 00:38:39 +1200
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

>Does this mean that I can't call any member functions of a class which is
>passed as a const-reference without risking modification of the class data?

No, that's fine, what you have. You just need to mark the member function to
show that it is one that doesn't attempt to modify the object:

class foo {
public:
  void member() const { your_code_here(); }
}

The const on the end of the member function means that it can be invoked for
const objects:

foo const f;
f.member();

or

bar(f);

Endlisnis wrote in message <3787A70E DOT 190417A AT unb DOT ca>...
>    I have some class "foo":
>class foo {...};
>
>And I have some function bar:
>void bar(const foo& foo2)
>{
> foo2.member();
>}
>
>    This generates a "warning: passing `const foo' as `this' argument of
`void
>foo::member()' discards const".
>Does this mean that I can't call any member functions of a class which is
>passed as a const-reference without risking modification of the class data?
I
>could just remove the 'const', but I did it to prevent other warning
messages
>like if I were to call "bar((foo)5)".
>--
>     (\/) Endlisnis (\/)
>          s257m AT unb DOT ca
>          Endlisnis AT HotMail DOT com
>          ICQ: 32959047
>
>