Rails spinoffs - May 2008 - static private and multi-inherit

/*author:csf178-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org*/
function Class(Initalizer,SuperClasses)
{
	if(!SuperClasses)SuperClasses=[];
	var ret=function(){
		for(var i=0;i<SuperClasses.length;i++)
		{
			SuperClasses[i].call(this);
		}

		var $private={};
		var $public=this;
		var $static=ret;

		with($static){
			with($private){
				with($public){
					eval("("+Initalizer+").apply(this,arguments)");
				}
			}
		}
		return this;
	}

	ret.prototype=Initalizer.prototype;

	for(var p in
Initalizer.prototype)ret.prototype[p]=Initalizer.prototype[p];
	for(var p in Initalizer)ret[p]=Initalizer[p];
	for(var i=0;i<SuperClasses.length;i++)
	{
		for(var p in SuperClasses[i].prototype)
		{
			ret.prototype[p]=SuperClasses[i].prototype[p]
		}
	}
	return ret;
}

/*
function alert(s)
{
	WScript.echo(s);
}
*/

/***********************************************
Example：public static private
************************************************/

var test1=new Class(function(){

	//v1 is public
	$public.v1=1;

	//v2 is private
	$private.v2=2;

	//define public variable with this
	this.vv1=2;

	//public function member
	$public.show=function(){
		//visit public and private variable
		alert(v1);
		alert(v2);
	}
	$public.set_static=function(v){
		$static.v3=v;
	}
});

var obj=new test1();

//visit public variable
alert(obj.v1);
alert(obj.vv1);

//try to visit private variable
alert(obj.v2);

//call public member function
obj.show();

//set static variable
obj.set_static(10);
//visit static variable from class
alert(test1.v3);

/***********************************************
Example:multi-inherit
************************************************/
var parent=function(){this.v4=6};
parent.prototype.v5=1000;

var test2=new Class(function(){
	$public.show2=function(){
		alert(this.v1);
		alert(v4);
		alert(v5);
	}
},[test1,parent]);

var obj=new test2();
obj.show2();
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>                 with($static){
>                         with($private){
>                                 with($public){
>                                        
eval("("+Initalizer+").apply(this,arguments)");
>                                 }
>                         }
>                 }
>                 return this;
>         }
Wonderful... : )
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>                 with($static){
>                         with($private){
>                                 with($public){
>                                        
eval("("+Initalizer+").apply(this,arguments)");
>                                 }
>                         }
>                 }
I think I just heard Crockford explode.

-- T.J. ;-)

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Actually, Firebug does something similar (double or triple "with"
wrapping, I''m guessing to have proper precedence), but "eval"
seems
unnecessary here.

- kangax

On May 13, 4:51 pm, "T.J. Crowder"
<tjcrow...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> >                 with($static){
> >                         with($private){
> >                                 with($public){
> >                                        
eval("("+Initalizer+").apply(this,arguments)");
> >                                 }
> >                         }
> >                 }
>
> I think I just heard Crockford explode.
>
> -- T.J. ;-)
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"eval" is necessary and it will not cost as much as you think.

On 5月14日, 上午4时56分, kangax <kan...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> Actually, Firebug does something similar (double or triple "with"
> wrapping, I''m guessing to have proper precedence), but
"eval" seems
> unnecessary here.
>
> - kangax
>
> On May 13, 4:51 pm, "T.J. Crowder"
<tjcrow...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
>
>
> > >                 with($static){
> > >                         with($private){
> > >                                 with($public){
> > >                                        
eval("("+Initalizer+").apply(this,arguments)");
> > >                                 }
> > >                         }
> > >                 }
>
> > I think I just heard Crockford explode.
>
> > -- T.J. ;-)- 隐藏被引用文字 -
>
> - 显示引用的文字 -
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Hi,

It''s certainly an interesting approach. :-)  Some observations:

1. It works; kudos.  It''s a bit like a dog riding a bicycle, but
still...

2. You''d have to document like *crazy* the fact that the code passed
to the Class function *isn''t* evaluated in the apparent lexical scope,
but rather in the really very special lexical scope created within the
Class function.  (Well, actually, it''s evaluated in both, but the
second is the one that will get used.)  Users failing to appreciate
the subtleties related to that would tend to run into difficult-to-
track-down bugs, particularly related to closures.  And *they''d* have
to document it like crazy in their own code, as well, so anyone
picking it up is forewarned.  Maintenance nightmares loom.

3. Debugging would tend to be fairly difficult, what with the class
and all of its member functions being within the eval, not (again)
actually where they appear to be.  I expect over time that JavaScript
debuggers will handle debugging eval''d code more and more elegantly
(certainly there is effort being made there), but for the moment...

4. The code for classes defined in this way is evaluated twice, once
in the course of the main script being evaluated, and then again when
Class is called.  Given that page load times are king, this isn''t
ideal although I''m sure it happens fairly quickly.

5. Regarding this:
>         ret.prototype=Initalizer.prototype;
>
>         for(var p in
> Initalizer.prototype)ret.prototype[p]=Initalizer.prototype[p];
Given the assignment in the first line, what is the purpose of the
loop following it?  Genuine question, not a dig -- am I missing a
subtlety?  Seems likely I am.

6. Style point:  You declare ''p'' at least three times, which
various
lint tools may complain about although it''s allowed by the ECMA spec.
(It Really Shouldn''t Be, but it is.)

Thanks for the post -- it''s interesting.  Very much about tradeoffs,
cost/benefit.  For me, most of the time, I think the cost would tend
to be too high, but it''s still an interesting approach to the old
problem.
--
T.J. Crowder
tj / crowder software / com

On May 13, 7:22 pm, "csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org"
<csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> /*author:csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org*/
> function Class(Initalizer,SuperClasses)
> {
>         if(!SuperClasses)SuperClasses=[];
>         var ret=function(){
>                 for(var i=0;i<SuperClasses.length;i++)
>                 {
>                         SuperClasses[i].call(this);
>                 }
>
>                 var $private={};
>                 var $public=this;
>                 var $static=ret;
>
>                 with($static){
>                         with($private){
>                                 with($public){
>                                        
eval("("+Initalizer+").apply(this,arguments)");
>                                 }
>                         }
>                 }
>                 return this;
>         }
>
>         ret.prototype=Initalizer.prototype;
>
>         for(var p in
> Initalizer.prototype)ret.prototype[p]=Initalizer.prototype[p];
>         for(var p in Initalizer)ret[p]=Initalizer[p];
>         for(var i=0;i<SuperClasses.length;i++)
>         {
>                 for(var p in SuperClasses[i].prototype)
>                 {
>                         ret.prototype[p]=SuperClasses[i].prototype[p]
>                 }
>         }
>         return ret;
>
> }
>
> /*
> function alert(s)
> {
>         WScript.echo(s);}
>
> */
>
> /***********************************************
> Example：public static private
> ************************************************/
>
> var test1=new Class(function(){
>
>         //v1 is public
>         $public.v1=1;
>
>         //v2 is private
>         $private.v2=2;
>
>         //define public variable with this
>         this.vv1=2;
>
>         //public function member
>         $public.show=function(){
>                 //visit public and private variable
>                 alert(v1);
>                 alert(v2);
>         }
>         $public.set_static=function(v){
>                 $static.v3=v;
>         }
>
> });
>
> var obj=new test1();
>
> //visit public variable
> alert(obj.v1);
> alert(obj.vv1);
>
> //try to visit private variable
> alert(obj.v2);
>
> //call public member function
> obj.show();
>
> //set static variable
> obj.set_static(10);
> //visit static variable from class
> alert(test1.v3);
>
> /***********************************************
> Example:multi-inherit
> ************************************************/
> var parent=function(){this.v4=6};
> parent.prototype.v5=1000;
>
> var test2=new Class(function(){
>         $public.show2=function(){
>                 alert(this.v1);
>                 alert(v4);
>                 alert(v5);
>         }
>
> },[test1,parent]);
>
> var obj=new test2();
> obj.show2();
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Thank you for reading it so carefully.
I''m not good at English but I will try my best to describe it clearly.

1. It''s a bit like a dog riding a bicycle.
I completely agree with you.
But don''t you think it is a bit like "Class.create" in
prototype?
I will never use it in my program myself.
It is just "a interesting code" for me.
I prefer to use functional programming(Later I may show you a
interesting implement of currying) or the following:
function class1()
{
    class2.call(this)//inherit
    class3.call(this)//multi-inherit
    this.v1=1;//public
    var v2=2;//private
}
class1.prototype.v3//do not use


2.It is used to create js class like class in java or c#
So member functions can only visit global variables no matter where
Initalizer is defined.

3.Eval cost much and is not friendly to debugger but it is the only
way to point [[scope]] to a normal object in scope chain.

4.I think we can ignore the cost in main script.
But in fact it is even worse, the code for classes defined in this way
is evaluated more than twice.
It is evaluated every time when creating a object from the class.


5. Sorry,I forget to delete "ret.prototype=Initalizer.prototype;"

6.I don''t think it is a bad style.In fact I like it very much......
:-)


On 5月14日, 下午6时54分, "T.J. Crowder" <tjcrow...@gmail.com>
wrote:
> Hi,
>
> It''s certainly an interesting approach. :-)  Some observations:
>
> 1. It works; kudos.  It''s a bit like a dog riding a bicycle, but
> still...
>
> 2. You''d have to document like *crazy* the fact that the code
passed
> to the Class function *isn''t* evaluated in the apparent lexical
scope,
> but rather in the really very special lexical scope created within the
> Class function.  (Well, actually, it''s evaluated in both, but the
> second is the one that will get used.)  Users failing to appreciate
> the subtleties related to that would tend to run into difficult-to-
> track-down bugs, particularly related to closures.  And *they''d*
have
> to document it like crazy in their own code, as well, so anyone
> picking it up is forewarned.  Maintenance nightmares loom.
>
> 3. Debugging would tend to be fairly difficult, what with the class
> and all of its member functions being within the eval, not (again)
> actually where they appear to be.  I expect over time that JavaScript
> debuggers will handle debugging eval''d code more and more
elegantly
> (certainly there is effort being made there), but for the moment...
>
> 4. The code for classes defined in this way is evaluated twice, once
> in the course of the main script being evaluated, and then again when
> Class is called.  Given that page load times are king, this isn''t
> ideal although I''m sure it happens fairly quickly.
>
> 5. Regarding this:
>
> >         ret.prototype=Initalizer.prototype;
>
> >         for(var p in
> > Initalizer.prototype)ret.prototype[p]=Initalizer.prototype[p];
>
> Given the assignment in the first line, what is the purpose of the
> loop following it?  Genuine question, not a dig -- am I missing a
> subtlety?  Seems likely I am.
>
> 6. Style point:  You declare ''p'' at least three times,
which various
> lint tools may complain about although it''s allowed by the ECMA
spec.
> (It Really Shouldn''t Be, but it is.)
>
> Thanks for the post -- it''s interesting.  Very much about
tradeoffs,
> cost/benefit.  For me, most of the time, I think the cost would tend
> to be too high, but it''s still an interesting approach to the old
> problem.
> --
> T.J. Crowder
> tj / crowder software / com
>
> On May 13, 7:22 pm,
"csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org"
<csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
>
>
> > /*author:csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org*/
> > function Class(Initalizer,SuperClasses)
> > {
> >         if(!SuperClasses)SuperClasses=[];
> >         var ret=function(){
> >                 for(var i=0;i<SuperClasses.length;i++)
> >                 {
> >                         SuperClasses[i].call(this);
> >                 }
>
> >                 var $private={};
> >                 var $public=this;
> >                 var $static=ret;
>
> >                 with($static){
> >                         with($private){
> >                                 with($public){
> >                                        
eval("("+Initalizer+").apply(this,arguments)");
> >                                 }
> >                         }
> >                 }
> >                 return this;
> >         }
>
> >         ret.prototype=Initalizer.prototype;
>
> >         for(var p in
> > Initalizer.prototype)ret.prototype[p]=Initalizer.prototype[p];
> >         for(var p in Initalizer)ret[p]=Initalizer[p];
> >         for(var i=0;i<SuperClasses.length;i++)
> >         {
> >                 for(var p in SuperClasses[i].prototype)
> >                 {
> >                         ret.prototype[p]=SuperClasses[i].prototype[p]
> >                 }
> >         }
> >         return ret;
>
> > }
>
> > /*
> > function alert(s)
> > {
> >         WScript.echo(s);}
>
> > */
>
> > /***********************************************
> > Example：public static private
> > ************************************************/
>
> > var test1=new Class(function(){
>
> >         //v1 is public
> >         $public.v1=1;
>
> >         //v2 is private
> >         $private.v2=2;
>
> >         //define public variable with this
> >         this.vv1=2;
>
> >         //public function member
> >         $public.show=function(){
> >                 //visit public and private variable
> >                 alert(v1);
> >                 alert(v2);
> >         }
> >         $public.set_static=function(v){
> >                 $static.v3=v;
> >         }
>
> > });
>
> > var obj=new test1();
>
> > //visit public variable
> > alert(obj.v1);
> > alert(obj.vv1);
>
> > //try to visit private variable
> > alert(obj.v2);
>
> > //call public member function
> > obj.show();
>
> > //set static variable
> > obj.set_static(10);
> > //visit static variable from class
> > alert(test1.v3);
>
> > /***********************************************
> > Example:multi-inherit
> > ************************************************/
> > var parent=function(){this.v4=6};
> > parent.prototype.v5=1000;
>
> > var test2=new Class(function(){
> >         $public.show2=function(){
> >                 alert(this.v1);
> >                 alert(v4);
> >                 alert(v5);
> >         }
>
> > },[test1,parent]);
>
> > var obj=new test2();
> > obj.show2();- 隐藏被引用文字 -
>
> - 显示引用的文字 -
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Hi,

(Your English seems very good indeed, FWIW.)

On #2:  Accessing members or globals aren''t the only things people
might do with initializers.  Hence the comment about closures.

On #6:  Well, it''s your call, as I say the spec does allow repeated
var declarations, although (again) if you use any lint tools, there''s
a warning you''re going to have to disable. :-)  But probably best not
to have style discussions here (or indeed at all, really, I shouldn''t
have brought it up).
--
T.J. Crowder
tj / crowder software / com

On May 14, 4:46 pm, "csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org"
<csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> Thank you for reading it so carefully.
> I''m not good at English but I will try my best to describe it
clearly.
>
> 1. It''s a bit like a dog riding a bicycle.
> I completely agree with you.
> But don''t you think it is a bit like "Class.create" in
prototype?
> I will never use it in my program myself.
> It is just "a interesting code" for me.
> I prefer to use functional programming(Later I may show you a
> interesting implement of currying) or the following:
> function class1()
> {
>     class2.call(this)//inherit
>     class3.call(this)//multi-inherit
>     this.v1=1;//public
>     var v2=2;//private}
>
> class1.prototype.v3//do not use
>
> 2.It is used to create js class like class in java or c#
> So member functions can only visit global variables no matter where
> Initalizer is defined.
>
> 3.Eval cost much and is not friendly to debugger but it is the only
> way to point [[scope]] to a normal object in scope chain.
>
> 4.I think we can ignore the cost in main script.
> But in fact it is even worse, the code for classes defined in this way
> is evaluated more than twice.
> It is evaluated every time when creating a object from the class.
>
> 5. Sorry,I forget to delete "ret.prototype=Initalizer.prototype;"
>
> 6.I don''t think it is a bad style.In fact I like it very
much......
> :-)
>
> On 5月14日, 下午6时54分, "T.J. Crowder" <tjcrow...@gmail.com>
wrote:
>
>
>
>
>
> > Hi,
>
> > It''s certainly an interesting approach. :-)  Some
observations:
>
> > 1. It works; kudos.  It''s a bit like a dog riding a bicycle,
but
> > still...
>
> > 2. You''d have to document like *crazy* the fact that the code
passed
> > to the Class function *isn''t* evaluated in the apparent
lexical scope,
> > but rather in the really very special lexical scope created within the
> > Class function.  (Well, actually, it''s evaluated in both, but
the
> > second is the one that will get used.)  Users failing to appreciate
> > the subtleties related to that would tend to run into difficult-to-
> > track-down bugs, particularly related to closures.  And
*they''d* have
> > to document it like crazy in their own code, as well, so anyone
> > picking it up is forewarned.  Maintenance nightmares loom.
>
> > 3. Debugging would tend to be fairly difficult, what with the class
> > and all of its member functions being within the eval, not (again)
> > actually where they appear to be.  I expect over time that JavaScript
> > debuggers will handle debugging eval''d code more and more
elegantly
> > (certainly there is effort being made there), but for the moment...
>
> > 4. The code for classes defined in this way is evaluated twice, once
> > in the course of the main script being evaluated, and then again when
> > Class is called.  Given that page load times are king, this
isn''t
> > ideal although I''m sure it happens fairly quickly.
>
> > 5. Regarding this:
>
> > >         ret.prototype=Initalizer.prototype;
>
> > >         for(var p in
> > > Initalizer.prototype)ret.prototype[p]=Initalizer.prototype[p];
>
> > Given the assignment in the first line, what is the purpose of the
> > loop following it?  Genuine question, not a dig -- am I missing a
> > subtlety?  Seems likely I am.
>
> > 6. Style point:  You declare ''p'' at least three
times, which various
> > lint tools may complain about although it''s allowed by the
ECMA spec.
> > (It Really Shouldn''t Be, but it is.)
>
> > Thanks for the post -- it''s interesting.  Very much about
tradeoffs,
> > cost/benefit.  For me, most of the time, I think the cost would tend
> > to be too high, but it''s still an interesting approach to the
old
> > problem.
> > --
> > T.J. Crowder
> > tj / crowder software / com
>
> > On May 13, 7:22 pm,
"csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org"
<csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > > /*author:csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org*/
> > > function Class(Initalizer,SuperClasses)
> > > {
> > >         if(!SuperClasses)SuperClasses=[];
> > >         var ret=function(){
> > >                 for(var i=0;i<SuperClasses.length;i++)
> > >                 {
> > >                         SuperClasses[i].call(this);
> > >                 }
>
> > >                 var $private={};
> > >                 var $public=this;
> > >                 var $static=ret;
>
> > >                 with($static){
> > >                         with($private){
> > >                                 with($public){
> > >                                        
eval("("+Initalizer+").apply(this,arguments)");
> > >                                 }
> > >                         }
> > >                 }
> > >                 return this;
> > >         }
>
> > >         ret.prototype=Initalizer.prototype;
>
> > >         for(var p in
> > > Initalizer.prototype)ret.prototype[p]=Initalizer.prototype[p];
> > >         for(var p in Initalizer)ret[p]=Initalizer[p];
> > >         for(var i=0;i<SuperClasses.length;i++)
> > >         {
> > >                 for(var p in SuperClasses[i].prototype)
> > >                 {
> > >                        
ret.prototype[p]=SuperClasses[i].prototype[p]
> > >                 }
> > >         }
> > >         return ret;
>
> > > }
>
> > > /*
> > > function alert(s)
> > > {
> > >         WScript.echo(s);}
>
> > > */
>
> > > /***********************************************
> > > Example：public static private
> > > ************************************************/
>
> > > var test1=new Class(function(){
>
> > >         //v1 is public
> > >         $public.v1=1;
>
> > >         //v2 is private
> > >         $private.v2=2;
>
> > >         //define public variable with this
> > >         this.vv1=2;
>
> > >         //public function member
> > >         $public.show=function(){
> > >                 //visit public and private variable
> > >                 alert(v1);
> > >                 alert(v2);
> > >         }
> > >         $public.set_static=function(v){
> > >                 $static.v3=v;
> > >         }
>
> > > });
>
> > > var obj=new test1();
>
> > > //visit public variable
> > > alert(obj.v1);
> > > alert(obj.vv1);
>
> > > //try to visit private variable
> > > alert(obj.v2);
>
> > > //call public member function
> > > obj.show();
>
> > > //set static variable
> > > obj.set_static(10);
> > > //visit static variable from class
> > > alert(test1.v3);
>
> > > /***********************************************
> > > Example:multi-inherit
> > > ************************************************/
> > > var parent=function(){this.v4=6};
> > > parent.prototype.v5=1000;
>
> > > var test2=new Class(function(){
> > >         $public.show2=function(){
> > >                 alert(this.v1);
> > >                 alert(v4);
> > >                 alert(v5);
> > >         }
>
> > > },[test1,parent]);
>
> > > var obj=new test2();
> > > obj.show2();- 隐藏被引用文字 -
>
> > - 显示引用的文字 -
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Thanks. :-)

On #2
I''m trying to make it closer to Java or C# than JavaScript.
So I think "Initalizer" should be considered as a class instead of a
function.

On #6
JavaScript is really a interesting language.

On 5月15日, 下午2时25分, "T.J. Crowder" <tjcrow...@gmail.com>
wrote:
> Hi,
>
> (Your English seems very good indeed, FWIW.)
>
> On #2:  Accessing members or globals aren''t the only things people
> might do with initializers.  Hence the comment about closures.
>
> On #6:  Well, it''s your call, as I say the spec does allow
repeated
> var declarations, although (again) if you use any lint tools,
there''s
> a warning you''re going to have to disable. :-)  But probably best
not
> to have style discussions here (or indeed at all, really, I
shouldn''t
> have brought it up).
> --
> T.J. Crowder
> tj / crowder software / com
>
> On May 14, 4:46 pm,
"csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org"
<csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
>
>
> > Thank you for reading it so carefully.
> > I''m not good at English but I will try my best to describe it
clearly.
>
> > 1. It''s a bit like a dog riding a bicycle.
> > I completely agree with you.
> > But don''t you think it is a bit like "Class.create"
in prototype?
> > I will never use it in my program myself.
> > It is just "a interesting code" for me.
> > I prefer to use functional programming(Later I may show you a
> > interesting implement of currying) or the following:
> > function class1()
> > {
> >     class2.call(this)//inherit
> >     class3.call(this)//multi-inherit
> >     this.v1=1;//public
> >     var v2=2;//private}
>
> > class1.prototype.v3//do not use
>
> > 2.It is used to create js class like class in java or c#
> > So member functions can only visit global variables no matter where
> > Initalizer is defined.
>
> > 3.Eval cost much and is not friendly to debugger but it is the only
> > way to point [[scope]] to a normal object in scope chain.
>
> > 4.I think we can ignore the cost in main script.
> > But in fact it is even worse, the code for classes defined in this way
> > is evaluated more than twice.
> > It is evaluated every time when creating a object from the class.
>
> > 5. Sorry,I forget to delete
"ret.prototype=Initalizer.prototype;"
>
> > 6.I don''t think it is a bad style.In fact I like it very
much......
> > :-)
>
> > On 5月14日, 下午6时54分, "T.J. Crowder"
<tjcrow...@gmail.com> wrote:
>
> > > Hi,
>
> > > It''s certainly an interesting approach. :-)  Some
observations:
>
> > > 1. It works; kudos.  It''s a bit like a dog riding a
bicycle, but
> > > still...
>
> > > 2. You''d have to document like *crazy* the fact that the
code passed
> > > to the Class function *isn''t* evaluated in the apparent
lexical scope,
> > > but rather in the really very special lexical scope created
within the
> > > Class function.  (Well, actually, it''s evaluated in
both, but the
> > > second is the one that will get used.)  Users failing to
appreciate
> > > the subtleties related to that would tend to run into
difficult-to-
> > > track-down bugs, particularly related to closures.  And
*they''d* have
> > > to document it like crazy in their own code, as well, so anyone
> > > picking it up is forewarned.  Maintenance nightmares loom.
>
> > > 3. Debugging would tend to be fairly difficult, what with the
class
> > > and all of its member functions being within the eval, not
(again)
> > > actually where they appear to be.  I expect over time that
JavaScript
> > > debuggers will handle debugging eval''d code more and
more elegantly
> > > (certainly there is effort being made there), but for the
moment...
>
> > > 4. The code for classes defined in this way is evaluated twice,
once
> > > in the course of the main script being evaluated, and then again
when
> > > Class is called.  Given that page load times are king, this
isn''t
> > > ideal although I''m sure it happens fairly quickly.
>
> > > 5. Regarding this:
>
> > > >         ret.prototype=Initalizer.prototype;
>
> > > >         for(var p in
> > > >
Initalizer.prototype)ret.prototype[p]=Initalizer.prototype[p];
>
> > > Given the assignment in the first line, what is the purpose of
the
> > > loop following it?  Genuine question, not a dig -- am I missing a
> > > subtlety?  Seems likely I am.
>
> > > 6. Style point:  You declare ''p'' at least three
times, which various
> > > lint tools may complain about although it''s allowed by
the ECMA spec.
> > > (It Really Shouldn''t Be, but it is.)
>
> > > Thanks for the post -- it''s interesting.  Very much
about tradeoffs,
> > > cost/benefit.  For me, most of the time, I think the cost would
tend
> > > to be too high, but it''s still an interesting approach
to the old
> > > problem.
> > > --
> > > T.J. Crowder
> > > tj / crowder software / com
>
> > > On May 13, 7:22 pm,
"csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org"
<csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > > > /*author:csf...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org*/
> > > > function Class(Initalizer,SuperClasses)
> > > > {
> > > >         if(!SuperClasses)SuperClasses=[];
> > > >         var ret=function(){
> > > >                 for(var i=0;i<SuperClasses.length;i++)
> > > >                 {
> > > >                         SuperClasses[i].call(this);
> > > >                 }
>
> > > >                 var $private={};
> > > >                 var $public=this;
> > > >                 var $static=ret;
>
> > > >                 with($static){
> > > >                         with($private){
> > > >                                 with($public){
> > > >                                        
eval("("+Initalizer+").apply(this,arguments)");
> > > >                                 }
> > > >                         }
> > > >                 }
> > > >                 return this;
> > > >         }
>
> > > >         ret.prototype=Initalizer.prototype;
>
> > > >         for(var p in
> > > >
Initalizer.prototype)ret.prototype[p]=Initalizer.prototype[p];
> > > >         for(var p in Initalizer)ret[p]=Initalizer[p];
> > > >         for(var i=0;i<SuperClasses.length;i++)
> > > >         {
> > > >                 for(var p in SuperClasses[i].prototype)
> > > >                 {
> > > >                        
ret.prototype[p]=SuperClasses[i].prototype[p]
> > > >                 }
> > > >         }
> > > >         return ret;
>
> > > > }
>
> > > > /*
> > > > function alert(s)
> > > > {
> > > >         WScript.echo(s);}
>
> > > > */
>
> > > > /***********************************************
> > > > Example：public static private
> > > > ************************************************/
>
> > > > var test1=new Class(function(){
>
> > > >         //v1 is public
> > > >         $public.v1=1;
>
> > > >         //v2 is private
> > > >         $private.v2=2;
>
> > > >         //define public variable with this
> > > >         this.vv1=2;
>
> > > >         //public function member
> > > >         $public.show=function(){
> > > >                 //visit public and private variable
> > > >                 alert(v1);
> > > >                 alert(v2);
> > > >         }
> > > >         $public.set_static=function(v){
> > > >                 $static.v3=v;
> > > >         }
>
> > > > });
>
> > > > var obj=new test1();
>
> > > > //visit public variable
> > > > alert(obj.v1);
> > > > alert(obj.vv1);
>
> > > > //try to visit private variable
> > > > alert(obj.v2);
>
> > > > //call public member function
> > > > obj.show();
>
> > > > //set static variable
> > > > obj.set_static(10);
> > > > //visit static variable from class
> > > > alert(test1.v3);
>
> > > > /***********************************************
> > > > Example:multi-inherit
> > > > ************************************************/
> > > > var parent=function(){this.v4=6};
> > > > parent.prototype.v5=1000;
>
> > > > var test2=new Class(function(){
> > > >         $public.show2=function(){
> > > >                 alert(this.v1);
> > > >                 alert(v4);
> > > >                 alert(v5);
> > > >         }
>
> > > > },[test1,parent]);
>
> > > > var obj=new test2();
> > > > obj.show2();- 隐藏被引用文字 -
>
> > > - 显示引用的文字 -- 隐藏被引用文字 -
>
> - 显示引用的文字 -
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