Re: gcc 3.0 template problem - only for C++ professionals or a bug ?

[Phil Edwards <pedwards at disaster dot jaj dot com>]

On Mon, Jul 23, 2001 at 10:23:41AM +0200, Helmut Schröger wrote:
> class namespace_t
> {
> public:
>         std::string name;
>         bool operator<(const namespace_t&);
                         ^^^^^

This 'const' tells the compiler that the namespace_t on the right-hand
side of the comparison is constant during the course of the comparison,
but you should also tell the compiler that the namespace_t on the left-hand
side will not be changed during the comparison.  The left-hand object is
'this' during the call to op<, and that is what is generating the warnings.

If you change both declaration and definition of op< to read

    bool operator<(const namespace_t&) const;

you will make op< a "const member function," which tells the compiler that
this function can safely be called by 'const' instances of namespace_t.


Phil

-- 
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