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static const function not allowed?

Hi,

I have something like

//
// common.h
const unsigned long m_dwStyle = 0x123;

//
// common.h
static BOOL Style( DWORD dw )const
{
return ((m_dwStyle&dw) ==dw);
};
//
//

But my compiler tells me "modifiers not allowed on static member functions".
But I cannot see what is wrong with the above.

Simon
May 10 '06
10 21382

Earl Purple wrote:
Rolf Magnus wrote:
Earl Purple wrote:
Actually it might make sense to mean "a static const member function
cannot modify any other static members".

But they haven't defined it that way.


It wouldn't be too useful though. For non-static members, the important
aspect is that it can be used on const objects (which of course means that
it doesn't modify the object). Since there is no object in a static member
functions, there is no real use for const.


It might have a use in meta-programming where you might use different
overloads, particularly in a multi-threaded environment. (A "const"
method would require only a read-lock whereas a "non-const" method
would require a write lock).

Of course, if that's what you want your design is probably wrong, and
I'm not intending to propose that they bring it into the standard. Am
just saying that it is not necessarily true that it "doesn't make
sense".


See also this message:

http://groups.google.com/group/comp....9e324fd0179a3f

Cheers! --M

May 10 '06 #11

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