Hi all,

I have a problem.

What is the best way to get a type TC from a type T where

T is int(foo::*)(char)

and

TC is int(foo::*)(char) const

I have tried

typdef T const TC

but with no success.

Thanks
Marco

On Apr 30, 12:38 pm, mcostalba gmail.com> wrote:

On Apr 30, 12:38 pm, mcostalba gmail.com> wrote:

These two types are completely different. A better way to understand the
meaning of these types is:

T ==> int (foo::*)(foo obj, char c)
TC ==> int (foo::*)(const foo obj, char c)

Thus, it is not the member function pointer which is const or non-const. It
is actually an argument of the member function that differs in const-ness.
This cannot be done with a static_cast or a const_cast.

You can use a reinterpret_cast to do this.

T x = &foo::abc;
TC y = reinterpret_cast(x);

but be careful when using the result of reinterpret_cast.

Hope this helps,
Devdatt

On Apr 30, 9:38 am, mcostalba gmail.com> wrote:

I'm assuming that you want to "synthesize" a member function pointer
type for a const class method - given a member function pointer for an
equivalent non-const class method. (Otherwise, it is not possible to
convert actual member pointer instances from one type to the another.)

In order to synthesize the const member function pointer type from the
non-const equivalent, I would declare a "helper" template like so:

// General helper template declared - but not defined

template
struct AddConstToMemberFunctionPtr;

On 1 Mag, 06:17, Greg Herlihy mac.com> wrote:

Yes, this is similar to what I have to do, actually I have to do the
contrary: detect pointer to const member functions.

On 1 May, 21:43, mcostalba gmail.com> wrote:

Take a look at is_call_possible metafunction, which was discussed
in this group before
(http://groups.google.com/group/comp.lang.c++.moderated/browse_thread/
thread/4f7c7a96f9afbe44/e5fbc9305539f699#e5fbc9305539f699).
It seems to do what you want.

HTH,
Roman Perepelitsa.

On 5 Mag, 15:09, "Roman.Perepeli...@gmail.com"
gmail.com> wrote:

Thanks Roman for your link.

Actually there are some good ideas in that implementation and I will
try to borrow a few of them...

Unfortunatly it does not fit the bill 100%%, indeed:

On 6 May, 08:57, mcostalba gmail.com> wrote:

Alexandre Courpron modified is_call_possible to create
is_exact_call_possible. You can find implementation here:
http://groups.google.co.uk/group/comp.lang.c++.moderated/browse_thread/thread/bd...#a56a91737e3f8c7c

Yes, you can use variadic templates (if your compiler supports then)
or boost::preprocessor to automate generation of specializations.

On 6 Mag, 16:21, "Roman.Perepeli...@gmail.com"
gmail.com> wrote:

I have quickly checked the link and it surely deserves a deeper read
when I found a bit of time.

Anyhow here is my much simpler solution...so simple that is probably
broken in some way, but I cannot find where:

/* Check if a function/functor Fun has a given signature Sig */
template
struct is_compatible
{
typedef typename boost::remove_pointer::type F;