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I had an idea the other day, and wondered what people might think of it. It
can be slightly hard for me to describe the concept, but I'll do my best. I
expect that there is some aspects of this that I haven't thought of that
may make it undesirable, but that's what discussion is for :-)

Consider some structs like the following:

struct A {
    struct B {
        int get_member() const {
            // hmm, how would we get access to A::member without some dirty
tricks?
        }
    };
    B b;
    int member = 123;
};



I have found that there are some circumstances (which I'll give some at the
end) where it would be useful for a member function of an object of type B,
to be able to get access to the object that it is encapsulated it.
Something along the lines of this:

struct A {
    struct B [[encapsulated]] {
        int get_member() const {
            A *p = encapsulator<A*>();
            return p->123;
        }
    };
    B b;
    int member = 123;
};

The idea being that the [[encapsulated]] attribute would cause the compiler
to automatically track a pointer to the encapsulating class, which is
accessible via an encapsulator() method (or whatever we choose to call this
thing), that returns a pointer to an object of type A, that this is
encapsulated in. Essentially it could be shorthand for the following:

struct A {
    struct B {
        int get_member() const {
            auto p = reinterpret_cast<A *>(reinterpret_cast<char *>(this) -
offsetof(A, b)); //probably works? definitely not reusable...
            return p->123;
        }
    };
    B b;
    int member = 123;
};

Which of course is both hideous, and requires that I know the name of the
member represented by "this" before hand, making generic usage not very
likely (if possible). These things, at least in concept, the compiler can
easily track if it isn't already. The way that I conceive of this is that
similar to dynamic_cast, we could have a pointer version which returns
nullptr on failure, and a reference version that throws an exception. It is
also possible that the compiler could identify misuse at compile time and
simply throw an error.

So, here's my primary motivating example:

Properties at a library level:

template <class T, class Obj, T (Obj::*G)() const, void (Obj::*S)(T)>
struct Property  {
    Obj& operator=(const T &value) {
        auto p = encapsulator<Obj*>();
        (p->*S)(value);
        return *p; // we return the encapsulating object for intuitive
chaining
    }

    operator T () const {
        auto p = encapsulator<Obj*>();
        return (p->*G)();
    }
};


struct A {
public:
    Property<int, A, &A::getMember, &A::setMember> member;

public:
    int getMember() const { return member_; } // imagine that these are
complex routines
    void setMember(int v) { member_ = v; }    // and we couldn't get the
same behavior by making member_ public


private:
    int member_;
};


int main() {
    A a;
    a.member = 123;
    std::cout << a.member << "\n";
}


Is this idea simply crazy? Any merit to it? Anyway, thanks in advance for
any feedback :-)
Evan

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<div dir=3D"ltr">I had an idea the other day, and wondered what people migh=
t think of it. It can be slightly hard for me to describe the concept, but =
I&#39;ll do my best. I expect that there is some aspects of this that I hav=
en&#39;t thought of that may make it undesirable, but that&#39;s what discu=
ssion is for :-)<br><br>Consider some structs like the following:<br><br><d=
iv class=3D"prettyprint" style=3D"background-color: rgb(250, 250, 250); bor=
der-color: rgb(187, 187, 187); border-style: solid; border-width: 1px; word=
-wrap: break-word;"><code class=3D"prettyprint"><div class=3D"subprettyprin=
t"><span style=3D"color: #008;" class=3D"styled-by-prettify">struct</span><=
span style=3D"color: #000;" class=3D"styled-by-prettify"> A </span><span st=
yle=3D"color: #660;" class=3D"styled-by-prettify">{</span><span style=3D"co=
lor: #000;" class=3D"styled-by-prettify"> =C2=A0 =C2=A0<br>=C2=A0 =C2=A0 </=
span><span style=3D"color: #008;" class=3D"styled-by-prettify">struct</span=
><span style=3D"color: #000;" class=3D"styled-by-prettify"> B </span><span =
style=3D"color: #660;" class=3D"styled-by-prettify">{</span><span style=3D"=
color: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =
</span><span style=3D"color: #008;" class=3D"styled-by-prettify">int</span>=
<span style=3D"color: #000;" class=3D"styled-by-prettify"> get_member</span=
><span style=3D"color: #660;" class=3D"styled-by-prettify">()</span><span s=
tyle=3D"color: #000;" class=3D"styled-by-prettify"> </span><span style=3D"c=
olor: #008;" class=3D"styled-by-prettify">const</span><span style=3D"color:=
 #000;" class=3D"styled-by-prettify"> </span><span style=3D"color: #660;" c=
lass=3D"styled-by-prettify">{</span><span style=3D"color: #000;" class=3D"s=
tyled-by-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><sp=
an style=3D"color: #800;" class=3D"styled-by-prettify">// hmm, how would we=
 get access to A::member without some dirty tricks?</span><span style=3D"co=
lor: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 </=
span><span style=3D"color: #660;" class=3D"styled-by-prettify">}</span><spa=
n style=3D"color: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 </s=
pan><span style=3D"color: #660;" class=3D"styled-by-prettify">};</span><spa=
n style=3D"color: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 B b=
</span><span style=3D"color: #660;" class=3D"styled-by-prettify">;</span><s=
pan style=3D"color: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 <=
/span><span style=3D"color: #008;" class=3D"styled-by-prettify">int</span><=
span style=3D"color: #000;" class=3D"styled-by-prettify"> member</span><fon=
t color=3D"#666600"><span style=3D"color: #000;" class=3D"styled-by-prettif=
y"> </span><span style=3D"color: #660;" class=3D"styled-by-prettify">=3D</s=
pan><span style=3D"color: #000;" class=3D"styled-by-prettify"> </span><span=
 style=3D"color: #066;" class=3D"styled-by-prettify">123</span><span style=
=3D"color: #660;" class=3D"styled-by-prettify">;</span></font><span style=
=3D"color: #000;" class=3D"styled-by-prettify"><br></span><span style=3D"co=
lor: #660;" class=3D"styled-by-prettify">};</span><span style=3D"color: #00=
0;" class=3D"styled-by-prettify"><br><br></span></div></code></div><div><br=
><br></div><div>I have found that there are some circumstances (which I&#39=
;ll give some at the end) where it would be useful for a member function of=
 an object of type B, to be able to get access to the object that it is enc=
apsulated it. Something along the lines of this:<br><br></div><div><div cla=
ss=3D"prettyprint" style=3D"background-color: rgb(250, 250, 250); border-co=
lor: rgb(187, 187, 187); border-style: solid; border-width: 1px; word-wrap:=
 break-word;"><code class=3D"prettyprint"><div class=3D"subprettyprint"><sp=
an style=3D"color: #008;" class=3D"styled-by-prettify">struct</span><span s=
tyle=3D"color: #000;" class=3D"styled-by-prettify"> A </span><span style=3D=
"color: #660;" class=3D"styled-by-prettify">{</span><span style=3D"color: #=
000;" class=3D"styled-by-prettify"> =C2=A0 =C2=A0<br>=C2=A0 =C2=A0 </span><=
span style=3D"color: #008;" class=3D"styled-by-prettify">struct</span><span=
 style=3D"color: #000;" class=3D"styled-by-prettify"> B </span><span style=
=3D"color: #660;" class=3D"styled-by-prettify">[[</span><span style=3D"colo=
r: #000;" class=3D"styled-by-prettify">encapsulated</span><span style=3D"co=
lor: #660;" class=3D"styled-by-prettify">]]</span><span style=3D"color: #00=
0;" class=3D"styled-by-prettify"> </span><span style=3D"color: #660;" class=
=3D"styled-by-prettify">{</span><span style=3D"color: #000;" class=3D"style=
d-by-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><span style=3D"color:=
 #008;" class=3D"styled-by-prettify">int</span><span style=3D"color: #000;"=
 class=3D"styled-by-prettify"> get_member</span><span style=3D"color: #660;=
" class=3D"styled-by-prettify">()</span><span style=3D"color: #000;" class=
=3D"styled-by-prettify"> </span><span style=3D"color: #008;" class=3D"style=
d-by-prettify">const</span><span style=3D"color: #000;" class=3D"styled-by-=
prettify"> </span><span style=3D"color: #660;" class=3D"styled-by-prettify"=
>{</span><span style=3D"color: #000;" class=3D"styled-by-prettify"><br>=C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 A </span><span style=3D"color: #660;=
" class=3D"styled-by-prettify">*</span><span style=3D"color: #000;" class=
=3D"styled-by-prettify">p </span><span style=3D"color: #660;" class=3D"styl=
ed-by-prettify">=3D</span><span style=3D"color: #000;" class=3D"styled-by-p=
rettify"> encapsulator</span><span style=3D"color: #660;" class=3D"styled-b=
y-prettify">&lt;</span><span style=3D"color: #000;" class=3D"styled-by-pret=
tify">A</span><span style=3D"color: #660;" class=3D"styled-by-prettify">*&g=
t;();</span><span style=3D"color: #000;" class=3D"styled-by-prettify"><br>=
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><span style=3D"color: #008=
;" class=3D"styled-by-prettify">return</span><span style=3D"color: #000;" c=
lass=3D"styled-by-prettify"> p</span><span style=3D"color: #660;" class=3D"=
styled-by-prettify">-&gt;</span><span style=3D"color: #066;" class=3D"style=
d-by-prettify">123</span><span style=3D"color: #660;" class=3D"styled-by-pr=
ettify">;</span><span style=3D"color: #000;" class=3D"styled-by-prettify"><=
br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><span style=3D"color: #660;" class=3D=
"styled-by-prettify">}</span><span style=3D"color: #000;" class=3D"styled-b=
y-prettify"><br>=C2=A0 =C2=A0 </span><span style=3D"color: #660;" class=3D"=
styled-by-prettify">};</span><span style=3D"color: #000;" class=3D"styled-b=
y-prettify"><br>=C2=A0 =C2=A0 B b</span><span style=3D"color: #660;" class=
=3D"styled-by-prettify">;</span><span style=3D"color: #000;" class=3D"style=
d-by-prettify"><br>=C2=A0 =C2=A0 </span><span style=3D"color: #008;" class=
=3D"styled-by-prettify">int</span><span style=3D"color: #000;" class=3D"sty=
led-by-prettify"> member </span><span style=3D"color: #660;" class=3D"style=
d-by-prettify">=3D</span><span style=3D"color: #000;" class=3D"styled-by-pr=
ettify"> </span><span style=3D"color: #066;" class=3D"styled-by-prettify">1=
23</span><span style=3D"color: #660;" class=3D"styled-by-prettify">;</span>=
<span style=3D"color: #000;" class=3D"styled-by-prettify"><br></span><span =
style=3D"color: #660;" class=3D"styled-by-prettify">};</span></div></code><=
/div><div class=3D"subprettyprint" style=3D"font-family: monospace; backgro=
und-color: rgb(250, 250, 250);"><br></div></div><div>The idea being that th=
e=C2=A0<span style=3D"background-color: rgb(250, 250, 250); color: rgb(0, 0=
, 0); font-family: monospace;">[[encapsulated]] </span><span style=3D"backg=
round-color: rgb(250, 250, 250); color: rgb(0, 0, 0);"><font face=3D"arial,=
 sans-serif">attribute would cause the compiler to automatically track a po=
inter to the encapsulating class, which is accessible via an=C2=A0</font></=
span><span style=3D"background-color: rgb(250, 250, 250); color: rgb(0, 0, =
0);"><font face=3D"monospace">encapsulator() </font><font face=3D"arial, sa=
ns-serif">method</font><font size=3D"2" face=3D"arial, sans-serif"> (or wha=
tever we choose to call this thing), that returns a pointer to an object of=
 type A, that=C2=A0</font></span><span style=3D"background-color: rgb(250, =
250, 250); color: rgb(0, 0, 136); font-family: monospace;">this=C2=A0</span=
><span style=3D"background-color: rgb(250, 250, 250);"><font color=3D"#0000=
00" face=3D"arial, sans-serif" size=3D"2">is encapsulated in. Essentially i=
t could be shorthand=C2=A0for the following:</font></span><br></div><div><s=
pan style=3D"background-color: rgb(250, 250, 250); color: rgb(0, 0, 0); fon=
t-family: arial, sans-serif; font-size: small;"><br></span></div><div class=
=3D"prettyprint" style=3D"background-color: rgb(250, 250, 250); border-colo=
r: rgb(187, 187, 187); border-style: solid; border-width: 1px; word-wrap: b=
reak-word;"><code class=3D"prettyprint"><div class=3D"subprettyprint"><span=
 style=3D"color: #008;" class=3D"styled-by-prettify">struct</span><span sty=
le=3D"color: #000;" class=3D"styled-by-prettify"> A </span><span style=3D"c=
olor: #660;" class=3D"styled-by-prettify">{</span><span style=3D"color: #00=
0;" class=3D"styled-by-prettify"> =C2=A0 =C2=A0<br>=C2=A0 =C2=A0 </span><sp=
an style=3D"color: #008;" class=3D"styled-by-prettify">struct</span><span s=
tyle=3D"color: #000;" class=3D"styled-by-prettify"> B </span><span style=3D=
"color: #660;" class=3D"styled-by-prettify">{</span><span style=3D"color: #=
000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><=
span style=3D"color: #008;" class=3D"styled-by-prettify">int</span><span st=
yle=3D"color: #000;" class=3D"styled-by-prettify"> get_member</span><span s=
tyle=3D"color: #660;" class=3D"styled-by-prettify">()</span><span style=3D"=
color: #000;" class=3D"styled-by-prettify"> </span><span style=3D"color: #0=
08;" class=3D"styled-by-prettify">const</span><span style=3D"color: #000;" =
class=3D"styled-by-prettify"> </span><span style=3D"color: #660;" class=3D"=
styled-by-prettify">{</span><span style=3D"color: #000;" class=3D"styled-by=
-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><span style=
=3D"color: #008;" class=3D"styled-by-prettify">auto</span><span style=3D"co=
lor: #000;" class=3D"styled-by-prettify"> p </span><span style=3D"color: #6=
60;" class=3D"styled-by-prettify">=3D</span><span style=3D"color: #000;" cl=
ass=3D"styled-by-prettify"> </span><span style=3D"color: #008;" class=3D"st=
yled-by-prettify">reinterpret_cast</span><span style=3D"color: #660;" class=
=3D"styled-by-prettify">&lt;</span><span style=3D"color: #000;" class=3D"st=
yled-by-prettify">A </span><span style=3D"color: #660;" class=3D"styled-by-=
prettify">*&gt;(</span><span style=3D"color: #008;" class=3D"styled-by-pret=
tify">reinterpret_cast</span><span style=3D"color: #660;" class=3D"styled-b=
y-prettify">&lt;</span><span style=3D"color: #008;" class=3D"styled-by-pret=
tify">char</span><span style=3D"color: #000;" class=3D"styled-by-prettify">=
 </span><span style=3D"color: #660;" class=3D"styled-by-prettify">*&gt;(</s=
pan><span style=3D"color: #008;" class=3D"styled-by-prettify">this</span><s=
pan style=3D"color: #660;" class=3D"styled-by-prettify">)</span><span style=
=3D"color: #000;" class=3D"styled-by-prettify"> </span><span style=3D"color=
: #660;" class=3D"styled-by-prettify">-</span><span style=3D"color: #000;" =
class=3D"styled-by-prettify"> offsetof</span><span style=3D"color: #660;" c=
lass=3D"styled-by-prettify">(</span><span style=3D"color: #000;" class=3D"s=
tyled-by-prettify">A</span><span style=3D"color: #660;" class=3D"styled-by-=
prettify">,</span><span style=3D"color: #000;" class=3D"styled-by-prettify"=
> b</span><span style=3D"color: #660;" class=3D"styled-by-prettify">));</sp=
an><span style=3D"color: #000;" class=3D"styled-by-prettify"> </span><span =
style=3D"color: #800;" class=3D"styled-by-prettify">//probably works? defin=
itely not reusable...</span><span style=3D"color: #000;" class=3D"styled-by=
-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><span style=
=3D"color: #008;" class=3D"styled-by-prettify">return</span><span style=3D"=
color: #000;" class=3D"styled-by-prettify"> p</span><span style=3D"color: #=
660;" class=3D"styled-by-prettify">-&gt;</span><span style=3D"color: #066;"=
 class=3D"styled-by-prettify">123</span><span style=3D"color: #660;" class=
=3D"styled-by-prettify">;</span><span style=3D"color: #000;" class=3D"style=
d-by-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><span style=3D"color:=
 #660;" class=3D"styled-by-prettify">}</span><span style=3D"color: #000;" c=
lass=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 </span><span style=3D"color: =
#660;" class=3D"styled-by-prettify">};</span><span style=3D"color: #000;" c=
lass=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 B b</span><span style=3D"colo=
r: #660;" class=3D"styled-by-prettify">;</span><span style=3D"color: #000;"=
 class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 </span><span style=3D"color=
: #008;" class=3D"styled-by-prettify">int</span><span style=3D"color: #000;=
" class=3D"styled-by-prettify"> member </span><span style=3D"color: #660;" =
class=3D"styled-by-prettify">=3D</span><span style=3D"color: #000;" class=
=3D"styled-by-prettify"> </span><span style=3D"color: #066;" class=3D"style=
d-by-prettify">123</span><span style=3D"color: #660;" class=3D"styled-by-pr=
ettify">;</span><span style=3D"color: #000;" class=3D"styled-by-prettify"><=
br></span><span style=3D"color: #660;" class=3D"styled-by-prettify">};</spa=
n></div></code></div><div><br><span style=3D"background-color: rgb(250, 250=
, 250);"><font color=3D"#000000" face=3D"arial, sans-serif" size=3D"2">Whic=
h of course is both hideous, and requires that I know the name of the membe=
r represented by &quot;this&quot; before hand, making generic usage not ver=
y likely (if possible). These things, at least in concept, the compiler can=
 easily track if it isn&#39;t already. The way that I conceive of this is t=
hat similar=C2=A0to dynamic_cast, we could have a pointer version which ret=
urns nullptr on failure, and a reference version=C2=A0that throws an except=
ion. It is also possible that the compiler could identify misuse=C2=A0at co=
mpile time and simply throw an error.</font></span></div><div><br></div><di=
v><span style=3D"background-color: rgb(250, 250, 250); color: rgb(0, 0, 0);=
 font-family: arial, sans-serif; font-size: small;">So, here&#39;s my prima=
ry motivating example:</span><br></div><div><span style=3D"background-color=
: rgb(250, 250, 250);"><br>Properties at a library level:</span></div><div>=
<span style=3D"background-color: rgb(250, 250, 250);"><br></span></div><div=
><span style=3D"background-color: rgb(250, 250, 250);"><div class=3D"pretty=
print" style=3D"background-color: rgb(250, 250, 250); border-color: rgb(187=
, 187, 187); border-style: solid; border-width: 1px; word-wrap: break-word;=
"><code class=3D"prettyprint"><div class=3D"subprettyprint"><span style=3D"=
color: #008;" class=3D"styled-by-prettify">template</span><span style=3D"co=
lor: #000;" class=3D"styled-by-prettify"> </span><span style=3D"color: #660=
;" class=3D"styled-by-prettify">&lt;</span><span style=3D"color: #008;" cla=
ss=3D"styled-by-prettify">class</span><span style=3D"color: #000;" class=3D=
"styled-by-prettify"> T</span><span style=3D"color: #660;" class=3D"styled-=
by-prettify">,</span><span style=3D"color: #000;" class=3D"styled-by-pretti=
fy"> </span><span style=3D"color: #008;" class=3D"styled-by-prettify">class=
</span><span style=3D"color: #000;" class=3D"styled-by-prettify"> </span><s=
pan style=3D"color: #606;" class=3D"styled-by-prettify">Obj</span><span sty=
le=3D"color: #660;" class=3D"styled-by-prettify">,</span><span style=3D"col=
or: #000;" class=3D"styled-by-prettify"> </span><font color=3D"#660066"><sp=
an style=3D"color: #000;" class=3D"styled-by-prettify">T</span></font><span=
 style=3D"color: #000;" class=3D"styled-by-prettify"> </span><span style=3D=
"color: #660;" class=3D"styled-by-prettify">(</span><span style=3D"color: #=
606;" class=3D"styled-by-prettify">Obj</span><span style=3D"color: #660;" c=
lass=3D"styled-by-prettify">::*</span><span style=3D"color: #000;" class=3D=
"styled-by-prettify">G</span><span style=3D"color: #660;" class=3D"styled-b=
y-prettify">)()</span><span style=3D"color: #000;" class=3D"styled-by-prett=
ify"> </span><span style=3D"color: #008;" class=3D"styled-by-prettify">cons=
t</span><span style=3D"color: #660;" class=3D"styled-by-prettify">,</span><=
span style=3D"color: #000;" class=3D"styled-by-prettify"> </span><span styl=
e=3D"color: #008;" class=3D"styled-by-prettify">void</span><span style=3D"c=
olor: #000;" class=3D"styled-by-prettify"> </span><span style=3D"color: #66=
0;" class=3D"styled-by-prettify">(</span><span style=3D"color: #606;" class=
=3D"styled-by-prettify">Obj</span><span style=3D"color: #660;" class=3D"sty=
led-by-prettify">::*</span><span style=3D"color: #000;" class=3D"styled-by-=
prettify">S</span><span style=3D"color: #660;" class=3D"styled-by-prettify"=
>)(</span><span style=3D"color: #000;" class=3D"styled-by-prettify">T</span=
><span style=3D"color: #660;" class=3D"styled-by-prettify">)&gt;</span><spa=
n style=3D"color: #000;" class=3D"styled-by-prettify"><br></span><span styl=
e=3D"color: #008;" class=3D"styled-by-prettify">struct</span><span style=3D=
"color: #000;" class=3D"styled-by-prettify"> </span><span style=3D"color: #=
606;" class=3D"styled-by-prettify">Property</span><span style=3D"color: #00=
0;" class=3D"styled-by-prettify"> =C2=A0</span><span style=3D"color: #660;"=
 class=3D"styled-by-prettify">{</span><span style=3D"color: #000;" class=3D=
"styled-by-prettify"><br>=C2=A0 =C2=A0 </span><span style=3D"color: #606;" =
class=3D"styled-by-prettify">Obj</span><span style=3D"color: #660;" class=
=3D"styled-by-prettify">&amp;</span><span style=3D"color: #000;" class=3D"s=
tyled-by-prettify"> </span><span style=3D"color: #008;" class=3D"styled-by-=
prettify">operator</span><span style=3D"color: #660;" class=3D"styled-by-pr=
ettify">=3D(</span><span style=3D"color: #008;" class=3D"styled-by-prettify=
">const</span><span style=3D"color: #000;" class=3D"styled-by-prettify"> T =
</span><span style=3D"color: #660;" class=3D"styled-by-prettify">&amp;</spa=
n><span style=3D"color: #000;" class=3D"styled-by-prettify">value</span><sp=
an style=3D"color: #660;" class=3D"styled-by-prettify">)</span><span style=
=3D"color: #000;" class=3D"styled-by-prettify"> </span><span style=3D"color=
: #660;" class=3D"styled-by-prettify">{</span><span style=3D"color: #000;" =
class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><font c=
olor=3D"#660066"><span style=3D"color: #008;" class=3D"styled-by-prettify">=
auto</span><span style=3D"color: #000;" class=3D"styled-by-prettify"> </spa=
n></font><span style=3D"color: #000;" class=3D"styled-by-prettify">p </span=
><span style=3D"color: #660;" class=3D"styled-by-prettify">=3D</span><span =
style=3D"color: #000;" class=3D"styled-by-prettify"> encapsulator</span><sp=
an style=3D"color: #660;" class=3D"styled-by-prettify">&lt;</span><span sty=
le=3D"color: #606;" class=3D"styled-by-prettify">Obj</span><span style=3D"c=
olor: #660;" class=3D"styled-by-prettify">*&gt;();</span><span style=3D"col=
or: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 </s=
pan><span style=3D"color: #660;" class=3D"styled-by-prettify">(</span><span=
 style=3D"color: #000;" class=3D"styled-by-prettify">p</span><span style=3D=
"color: #660;" class=3D"styled-by-prettify">-&gt;*</span><span style=3D"col=
or: #000;" class=3D"styled-by-prettify">S</span><span style=3D"color: #660;=
" class=3D"styled-by-prettify">)(</span><span style=3D"color: #000;" class=
=3D"styled-by-prettify">value</span><span style=3D"color: #660;" class=3D"s=
tyled-by-prettify">);</span><span style=3D"color: #000;" class=3D"styled-by=
-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><span style=3D"color: #00=
8;" class=3D"styled-by-prettify">return</span><span style=3D"color: #000;" =
class=3D"styled-by-prettify"> </span><span style=3D"color: #660;" class=3D"=
styled-by-prettify">*</span><span style=3D"color: #000;" class=3D"styled-by=
-prettify">p</span><span style=3D"color: #660;" class=3D"styled-by-prettify=
">;</span><span style=3D"color: #000;" class=3D"styled-by-prettify"> </span=
><span style=3D"color: #800;" class=3D"styled-by-prettify">// we return the=
 encapsulat</span><span style=3D"color: #800;" class=3D"styled-by-prettify"=
>ing object for intuitive chaining</span><span style=3D"color: #000;" class=
=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 </span><span style=3D"color: #660=
;" class=3D"styled-by-prettify">}</span><span style=3D"color: #000;" class=
=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 <br>=C2=A0 =C2=A0 </span><span st=
yle=3D"color: #008;" class=3D"styled-by-prettify">operator</span><span styl=
e=3D"color: #000;" class=3D"styled-by-prettify"> T </span><span style=3D"co=
lor: #660;" class=3D"styled-by-prettify">()</span><span style=3D"color: #00=
0;" class=3D"styled-by-prettify"> </span><span style=3D"color: #008;" class=
=3D"styled-by-prettify">const</span><span style=3D"color: #000;" class=3D"s=
tyled-by-prettify"> </span><span style=3D"color: #660;" class=3D"styled-by-=
prettify">{</span><span style=3D"color: #000;" class=3D"styled-by-prettify"=
><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><font color=3D"#660066"><span style=
=3D"color: #008;" class=3D"styled-by-prettify">auto</span><span style=3D"co=
lor: #000;" class=3D"styled-by-prettify"> </span></font><span style=3D"colo=
r: #000;" class=3D"styled-by-prettify">p </span><span style=3D"color: #660;=
" class=3D"styled-by-prettify">=3D</span><span style=3D"color: #000;" class=
=3D"styled-by-prettify"> encapsulator</span><span style=3D"color: #660;" cl=
ass=3D"styled-by-prettify">&lt;</span><span style=3D"color: #606;" class=3D=
"styled-by-prettify">Obj</span><span style=3D"color: #660;" class=3D"styled=
-by-prettify">*&gt;();</span><span style=3D"color: #000;" class=3D"styled-b=
y-prettify"><br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 </span><span style=3D"color: #0=
08;" class=3D"styled-by-prettify">return</span><span style=3D"color: #000;"=
 class=3D"styled-by-prettify"> </span><span style=3D"color: #660;" class=3D=
"styled-by-prettify">(</span><span style=3D"color: #000;" class=3D"styled-b=
y-prettify">p</span><font color=3D"#666600"><span style=3D"color: #660;" cl=
ass=3D"styled-by-prettify">-&gt;*</span></font><span style=3D"color: #000;"=
 class=3D"styled-by-prettify">G</span><span style=3D"color: #660;" class=3D=
"styled-by-prettify">)();</span><span style=3D"color: #000;" class=3D"style=
d-by-prettify"><br>=C2=A0 =C2=A0 </span><span style=3D"color: #660;" class=
=3D"styled-by-prettify">}</span><span style=3D"color: #000;" class=3D"style=
d-by-prettify"><br></span><span style=3D"color: #660;" class=3D"styled-by-p=
rettify">};</span><span style=3D"color: #000;" class=3D"styled-by-prettify"=
><br><br><br></span><span style=3D"color: #008;" class=3D"styled-by-prettif=
y">struct</span><span style=3D"color: #000;" class=3D"styled-by-prettify"> =
A </span><span style=3D"color: #660;" class=3D"styled-by-prettify">{</span>=
<span style=3D"color: #000;" class=3D"styled-by-prettify"><br></span><span =
style=3D"color: #008;" class=3D"styled-by-prettify">public</span><span styl=
e=3D"color: #660;" class=3D"styled-by-prettify">:</span><span style=3D"colo=
r: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 </span><span style=
=3D"color: #606;" class=3D"styled-by-prettify">Property</span><span style=
=3D"color: #660;" class=3D"styled-by-prettify">&lt;</span><span style=3D"co=
lor: #008;" class=3D"styled-by-prettify">int</span><span style=3D"color: #6=
60;" class=3D"styled-by-prettify">,</span><span style=3D"color: #000;" clas=
s=3D"styled-by-prettify"> A</span><span style=3D"color: #660;" class=3D"sty=
led-by-prettify">,</span><span style=3D"color: #000;" class=3D"styled-by-pr=
ettify"> </span><span style=3D"color: #660;" class=3D"styled-by-prettify">&=
amp;</span><span style=3D"color: #000;" class=3D"styled-by-prettify">A</spa=
n><span style=3D"color: #660;" class=3D"styled-by-prettify">::</span><span =
style=3D"color: #000;" class=3D"styled-by-prettify">getMember</span><span s=
tyle=3D"color: #660;" class=3D"styled-by-prettify">,</span><span style=3D"c=
olor: #000;" class=3D"styled-by-prettify"> </span><span style=3D"color: #66=
0;" class=3D"styled-by-prettify">&amp;</span><span style=3D"color: #000;" c=
lass=3D"styled-by-prettify">A</span><span style=3D"color: #660;" class=3D"s=
tyled-by-prettify">::</span><span style=3D"color: #000;" class=3D"styled-by=
-prettify">setMember</span><span style=3D"color: #660;" class=3D"styled-by-=
prettify">&gt;</span><span style=3D"color: #000;" class=3D"styled-by-pretti=
fy"> member</span><span style=3D"color: #660;" class=3D"styled-by-prettify"=
>;</span><span style=3D"color: #000;" class=3D"styled-by-prettify"><br><br>=
</span><span style=3D"color: #008;" class=3D"styled-by-prettify">public</sp=
an><span style=3D"color: #660;" class=3D"styled-by-prettify">:</span><span =
style=3D"color: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 </spa=
n><span style=3D"color: #008;" class=3D"styled-by-prettify">int</span><span=
 style=3D"color: #000;" class=3D"styled-by-prettify"> getMember</span><span=
 style=3D"color: #660;" class=3D"styled-by-prettify">()</span><span style=
=3D"color: #000;" class=3D"styled-by-prettify"> </span><span style=3D"color=
: #008;" class=3D"styled-by-prettify">const</span><span style=3D"color: #00=
0;" class=3D"styled-by-prettify"> </span><span style=3D"color: #660;" class=
=3D"styled-by-prettify">{</span><span style=3D"color: #000;" class=3D"style=
d-by-prettify"> </span><span style=3D"color: #008;" class=3D"styled-by-pret=
tify">return</span><span style=3D"color: #000;" class=3D"styled-by-prettify=
"> member_</span><span style=3D"color: #660;" class=3D"styled-by-prettify">=
;</span><span style=3D"color: #000;" class=3D"styled-by-prettify"> </span><=
span style=3D"color: #660;" class=3D"styled-by-prettify">}</span><span styl=
e=3D"color: #000;" class=3D"styled-by-prettify"> </span><span style=3D"colo=
r: #800;" class=3D"styled-by-prettify">// imagine that these are complex ro=
utines</span><span style=3D"color: #000;" class=3D"styled-by-prettify"><br>=
=C2=A0 =C2=A0 </span><span style=3D"color: #008;" class=3D"styled-by-pretti=
fy">void</span><span style=3D"color: #000;" class=3D"styled-by-prettify"> s=
etMember</span><span style=3D"color: #660;" class=3D"styled-by-prettify">(<=
/span><span style=3D"color: #008;" class=3D"styled-by-prettify">int</span><=
span style=3D"color: #000;" class=3D"styled-by-prettify"> v</span><span sty=
le=3D"color: #660;" class=3D"styled-by-prettify">)</span><span style=3D"col=
or: #000;" class=3D"styled-by-prettify"> </span><span style=3D"color: #660;=
" class=3D"styled-by-prettify">{</span><span style=3D"color: #000;" class=
=3D"styled-by-prettify"> member_ </span><span style=3D"color: #660;" class=
=3D"styled-by-prettify">=3D</span><span style=3D"color: #000;" class=3D"sty=
led-by-prettify"> v</span><span style=3D"color: #660;" class=3D"styled-by-p=
rettify">;</span><span style=3D"color: #000;" class=3D"styled-by-prettify">=
 </span><span style=3D"color: #660;" class=3D"styled-by-prettify">}</span><=
span style=3D"color: #000;" class=3D"styled-by-prettify"> =C2=A0 =C2=A0</sp=
an><span style=3D"color: #800;" class=3D"styled-by-prettify">// and we coul=
dn&#39;t get the same behavior by making member_ public</span><span style=
=3D"color: #000;" class=3D"styled-by-prettify"><br><br><br></span><span sty=
le=3D"color: #008;" class=3D"styled-by-prettify">private</span><span style=
=3D"color: #660;" class=3D"styled-by-prettify">:</span><span style=3D"color=
: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 </span><span style=
=3D"color: #008;" class=3D"styled-by-prettify">int</span><span style=3D"col=
or: #000;" class=3D"styled-by-prettify"> member_</span><span style=3D"color=
: #660;" class=3D"styled-by-prettify">;</span><span style=3D"color: #000;" =
class=3D"styled-by-prettify"><br></span><span style=3D"color: #660;" class=
=3D"styled-by-prettify">};</span><span style=3D"color: #000;" class=3D"styl=
ed-by-prettify"><br><br><br></span><span style=3D"color: #008;" class=3D"st=
yled-by-prettify">int</span><span style=3D"color: #000;" class=3D"styled-by=
-prettify"> main</span><span style=3D"color: #660;" class=3D"styled-by-pret=
tify">()</span><span style=3D"color: #000;" class=3D"styled-by-prettify"> <=
/span><span style=3D"color: #660;" class=3D"styled-by-prettify">{</span><sp=
an style=3D"color: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 A =
a</span><span style=3D"color: #660;" class=3D"styled-by-prettify">;</span><=
span style=3D"color: #000;" class=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 =
a</span><span style=3D"color: #660;" class=3D"styled-by-prettify">.</span><=
span style=3D"color: #000;" class=3D"styled-by-prettify">member </span><spa=
n style=3D"color: #660;" class=3D"styled-by-prettify">=3D</span><span style=
=3D"color: #000;" class=3D"styled-by-prettify"> </span><span style=3D"color=
: #066;" class=3D"styled-by-prettify">123</span><span style=3D"color: #660;=
" class=3D"styled-by-prettify">;</span><span style=3D"color: #000;" class=
=3D"styled-by-prettify"><br>=C2=A0 =C2=A0 std</span><span style=3D"color: #=
660;" class=3D"styled-by-prettify">::</span><span style=3D"color: #000;" cl=
ass=3D"styled-by-prettify">cout </span><span style=3D"color: #660;" class=
=3D"styled-by-prettify">&lt;&lt;</span><span style=3D"color: #000;" class=
=3D"styled-by-prettify"> a</span><span style=3D"color: #660;" class=3D"styl=
ed-by-prettify">.</span><span style=3D"color: #000;" class=3D"styled-by-pre=
ttify">member </span><span style=3D"color: #660;" class=3D"styled-by-pretti=
fy">&lt;&lt;</span><span style=3D"color: #000;" class=3D"styled-by-prettify=
"> </span><span style=3D"color: #080;" class=3D"styled-by-prettify">&quot;\=
n&quot;</span><span style=3D"color: #660;" class=3D"styled-by-prettify">;</=
span><span style=3D"color: #000;" class=3D"styled-by-prettify"><br></span><=
span style=3D"color: #660;" class=3D"styled-by-prettify">}</span></div></co=
de></div><div><br></div><div><br>Is this idea simply crazy? Any merit to it=
? Anyway, thanks in advance for any feedback :-)<br>Evan</div></span></div>=
</div>

<p></p>

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