HI

HI

[prasad inchal]

Hi ,

   I wanted to know the binding concept of C++
language.
 
 I have two issues regarding this,

 1: I want to have C++ to create class objects
dynamically, at runtime.
 2: I want to have an interpreter where in I can call
C++ member functions directly 
    with the respective obj and parameters.
 Thanks ,
 Prasad

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RE: C++ objects at runtime (was: HI)

[Rupert Wood]

prasad inchal wrote:

One general principle of C++ is to perform as many checks as possible at
compile-time - I don't think it qualifies as 'late-binding' (if you
could even apply that to a language - sounds more like linking to me).

> 1: I want to have C++ to create class objects dynamically, at
>    runtime.

If you mean create new instances of object types that you defined at
compile time, then yes - use the 'new' operator.

If you mean define new object types at run time, then no. I'm not sure
why you'd want to do this anyway. You could, I suppose, hack together a
run-time derivative and overload the virtual functions in a new vtable
but I don't know why you'd want to do this and I don't believe that
there's any support for this in the compiler - what you'd end up with
would be a nasty hack.

>  2: I want to have an interpreter where in I can call C++ member
>     functions directly with the respective obj and parameters.

No, not easily possible. Again, you need intimiate knowledge of the C++
ABI and mangling scheme; you'd need symbol information persisted beyond
the link stage and you'd need assembler chunks to construct the right
call state and make the call.

Hope that helps,
Rup.

RE: C++ objects at runtime (was: HI)

[Rupert Wood]

prasad inchal wrote:

One general principle of C++ is to perform as many checks as possible at
compile-time - I don't think it qualifies as 'late-binding' (if you
could even apply that to a language - sounds more like linking to me).

> 1: I want to have C++ to create class objects dynamically, at
>    runtime.

If you mean create new instances of object types that you defined at
compile time, then yes - use the 'new' operator.

If you mean define new object types at run time, then no. I'm not sure
why you'd want to do this anyway. You could, I suppose, hack together a
run-time derivative and overload the virtual functions in a new vtable
but I don't know why you'd want to do this and I don't believe that
there's any support for this in the compiler - what you'd end up with
would be a nasty hack.

>  2: I want to have an interpreter where in I can call C++ member
>     functions directly with the respective obj and parameters.

No, not easily possible. Again, you need intimiate knowledge of the C++
ABI and mangling scheme; you'd need symbol information persisted beyond
the link stage and you'd need assembler chunks to construct the right
call state and make the call.

Hope that helps,
Rup.

Re: HI

[Andrea 'Fyre Wyzard' Bocci]

At 23.42 25/11/01 (GMT -0800), prasad inchal wrote:
>Hi ,
>
>    I wanted to know the binding concept of C++
>language.
>
>  I have two issues regarding this,
>
>  1: I want to have C++ to create class objects
>dynamically, at runtime.
>  2: I want to have an interpreter where in I can call
>C++ member functions directly
>     with the respective obj and parameters.
>  Thanks ,
>  Prasad

I don't think this is a GCC related question...
Anyway:

What is that you EXACTLY want to do ?
1)
Dynamically reate new CLASSES or just OBJECTS of a specifc class ?
I don't think yuo can't do the former in c++, while for the second just 
define a class with

class my_class {
   ...
   class definition
   ...
};

and create objects with

my_class* my_object = new my_class(class parameters);

For more C++ programming info, have a look at 
<http://www.mindview.net/Books/TICPP/ThinkingInCPP2e.html>.

2)
That is, you need a c++ interpreter, not a compiler.
Have a look at <http://root.cern.ch/root/Cint.html>

HTH
fwyzard

Re: HI

[Frank Schafer]

[-- Attachment #1: Type: text/plain, Size: 662 bytes --]

prasad inchal wrote:

> Hi ,
>
>    I wanted to know the binding concept of C++
> language.
>
>  I have two issues regarding this,
>
>  1: I want to have C++ to create class objects
> dynamically, at runtime.
>  2: I want to have an interpreter where in I can call
> C++ member functions directly
>     with the respective obj and parameters.
>  Thanks ,
>  Prasad
>
> __________________________________________________
> Do You Yahoo!?
> Yahoo! GeoCities - quick and easy web site hosting, just $8.95/month.
> http://geocities.yahoo.com/ps/info1

Hi,

1: Every object IS generated dynamically.
2. See the PERL or Puthon bindings for C++.

Hope this helps
Frank

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org:SETUZA a.s.;IT
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email;internet:frank.schafer@setuza.cz
title:Dipl. Ing.
note:System administrator
x-mozilla-cpt:;0
fn:Frank Schafer
end:vcard

HI

[prasad inchal]

Hi ,

   I wanted to know the binding concept of C++
language.
 
 I have two issues regarding this,

 1: I want to have C++ to create class objects
dynamically, at runtime.
 2: I want to have an interpreter where in I can call
C++ member functions directly 
    with the respective obj and parameters.
 Thanks ,
 Prasad

__________________________________________________
Do You Yahoo!?
Yahoo! GeoCities - quick and easy web site hosting, just $8.95/month.
http://geocities.yahoo.com/ps/info1

RE: C++ objects at runtime (was: HI)

[Rupert Wood]

prasad inchal wrote:

One general principle of C++ is to perform as many checks as possible at
compile-time - I don't think it qualifies as 'late-binding' (if you
could even apply that to a language - sounds more like linking to me).

> 1: I want to have C++ to create class objects dynamically, at
>    runtime.

If you mean create new instances of object types that you defined at
compile time, then yes - use the 'new' operator.

If you mean define new object types at run time, then no. I'm not sure
why you'd want to do this anyway. You could, I suppose, hack together a
run-time derivative and overload the virtual functions in a new vtable
but I don't know why you'd want to do this and I don't believe that
there's any support for this in the compiler - what you'd end up with
would be a nasty hack.

>  2: I want to have an interpreter where in I can call C++ member
>     functions directly with the respective obj and parameters.

No, not easily possible. Again, you need intimiate knowledge of the C++
ABI and mangling scheme; you'd need symbol information persisted beyond
the link stage and you'd need assembler chunks to construct the right
call state and make the call.

Hope that helps,
Rup.

Re: HI

[Andrea 'Fyre Wyzard' Bocci]

At 23.42 25/11/01 (GMT -0800), prasad inchal wrote:
>Hi ,
>
>    I wanted to know the binding concept of C++
>language.
>
>  I have two issues regarding this,
>
>  1: I want to have C++ to create class objects
>dynamically, at runtime.
>  2: I want to have an interpreter where in I can call
>C++ member functions directly
>     with the respective obj and parameters.
>  Thanks ,
>  Prasad

I don't think this is a GCC related question...
Anyway:

What is that you EXACTLY want to do ?
1)
Dynamically reate new CLASSES or just OBJECTS of a specifc class ?
I don't think yuo can't do the former in c++, while for the second just 
define a class with

class my_class {
   ...
   class definition
   ...
};

and create objects with

my_class* my_object = new my_class(class parameters);

For more C++ programming info, have a look at 
< http://www.mindview.net/Books/TICPP/ThinkingInCPP2e.html >.

2)
That is, you need a c++ interpreter, not a compiler.
Have a look at < http://root.cern.ch/root/Cint.html >

HTH
fwyzard

Re: HI

[Frank Schafer]

prasad inchal wrote:

> Hi ,
>
>    I wanted to know the binding concept of C++
> language.
>
>  I have two issues regarding this,
>
>  1: I want to have C++ to create class objects
> dynamically, at runtime.
>  2: I want to have an interpreter where in I can call
> C++ member functions directly
>     with the respective obj and parameters.
>  Thanks ,
>  Prasad
>
> __________________________________________________
> Do You Yahoo!?
> Yahoo! GeoCities - quick and easy web site hosting, just $8.95/month.
> http://geocities.yahoo.com/ps/info1

Hi,

1: Every object IS generated dynamically.
2. See the PERL or Puthon bindings for C++.

Hope this helps
Frank