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Is anybody interested in the following extension to *std::function*? I
propose to add a constructor with
two arguments:

*template<class T>
function(T* obj1, R (T::*fx)(Arg ... ));*

Consider the following class:
*class A
{
    double x;
public:
    A(double x1):x(x1) {}
    double get() const { return x; }
    void add1(double& c) { x+= c; c = x;}
};*

It will be possible to write as follows:

*A a(10);*
*{
   function<void(double&)> a_add1(&a,&A::add1); // to create a delegate: to
bind an object with its member function.*
*
   double z;
   a_add1(z);
}*


First of all, the standard function + bind will not allow to do this.
It is also easier to use then bind (when using bind is possible);
especially in case when function has many parameters.

If the following definition is available
*template<class T, class R, class ... Arg>
function<R(Arg ...)> member_delegate(T* obj,R (T::*f)(Arg ... ))
{
    return function<R(Arg ...)>(obj, f);
}*

then we can even write shorter:
*auto a_add1 = member_delegate(&a, &A::add1);*


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<p>Is anybody interested in the following extension to <strong>std::functio=
n</strong>? I propose to add a constructor with <br>two arguments:</p><p><s=
trong>template&lt;class T&gt;<br>function(T* obj1, R (T::*fx)(Arg ... ));</=
strong></p><p>Consider the following class:<br><strong>class A<br>{<br>&nbs=
p;&nbsp;&nbsp; double x;<br>public:<br>&nbsp;&nbsp;&nbsp; A(double x1):x(x1=
) {}<br>&nbsp;&nbsp;&nbsp; double get() const { return x; }<br>&nbsp;&nbsp;=
&nbsp; void add1(double&amp; c) { x+=3D c; c =3D x;}<br>};</strong></p><p>I=
t will be possible to write as follows:</p><p><strong>A a(10);</strong></p>=
<div><strong>{<br>&nbsp;&nbsp; function&lt;void(double&amp;)&gt; a_add1(&am=
p;a,&amp;A::add1); // to create a delegate: to bind an object with its memb=
er function.</strong></div><div><strong><br>&nbsp;&nbsp; double z;<br>&nbsp=
;&nbsp; a_add1(z);<br>}</strong></div><p><br>First of all, the standard fun=
ction + bind will not allow to do this. <br>It is also easier to use then b=
ind (when using bind is possible); especially in case when function has man=
y parameters.</p><p>If the following definition is available<br><strong>tem=
plate&lt;class T, class R, class ... Arg&gt;<br>function&lt;R(Arg ...)&gt; =
member_delegate(T* obj,R (T::*f)(Arg ... ))<br>{<br>&nbsp;&nbsp;&nbsp; retu=
rn function&lt;R(Arg ...)&gt;(obj, f);<br>}</strong></p><p>then we can even=
 write shorter:</p><div><strong>auto a_add1 =3D member_delegate(&amp;a, &am=
p;A::add1);</strong><br></div><div>&nbsp;</div>

<p></p>

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