support for weak_ptr binding

[nobody]

Hello,

recently i faced with problem - i was not able to pass weak_ptr to bind() function. I started to study why and found there is no support for this in boost.

As result, me and my friend wrote "get_pointer" version
which accepts weak_ptr. 

At actual call moment, implementation uses weak_ptr::lock() to get shared_ptr. If retrieved shared_ptr is invalid, then exception of type "disposed_exception" thrown.

This code was tested on Windows XP SP2 with following compilers: VC6, VC7, VC7.1, VC8, g++ 3.2.3 (MinGW), g++ 3.4.4 (Cygwin).

If you find this code is useful for someone else me, please add to boost (it's actually not a library, this is why i'm poosting it to "patches"). You can find sources + test app in attachment.


Thank you,
Dmytro Gokun