Script Engine in C++

[fernandez.dan]

Hey I'm sorry if this is not the appropriate news group for this
question. I was wondering if anyone has any recommendation for
embbedding a script engine in a c++ application. I want to feed my C++
application scripts which based on the script would create C++ objects
and call the appropriate methods.

At the moment I created a simple interpreter within our C++ aplication
that we can feed our custom scripts. The interpreter is primitive and
it lacks alot of functionality that is why I am looking at other
alternatives.

I looked at spidermonkey to embed in my c++ application but it seems a
little cumbersome dealing with C++ objects. Does anyone have any other
recommendations?

[Victor Bazarov]

fe***********@gmail.com wrote:

Hey I'm sorry if this is not the appropriate news group for this
question. I was wondering if anyone has any recommendation for
embbedding a script engine in a c++ application. I want to feed my C++
application scripts which based on the script would create C++ objects
and call the appropriate methods.

At the moment I created a simple interpreter within our C++ aplication
that we can feed our custom scripts. The interpreter is primitive and
it lacks alot of functionality that is why I am looking at other
alternatives.

I looked at spidermonkey to embed in my c++ application but it seems a
little cumbersome dealing with C++ objects. Does anyone have any other
recommendations?

Python should probably work for most platforms.

V

[Ioannis Vranos]

fe***********@gmail.com wrote:

Hey I'm sorry if this is not the appropriate news group for this
question. I was wondering if anyone has any recommendation for
embbedding a script engine in a c++ application. I want to feed my C++
application scripts which based on the script would create C++ objects
and call the appropriate methods.

At the moment I created a simple interpreter within our C++ aplication
that we can feed our custom scripts. The interpreter is primitive and
it lacks alot of functionality that is why I am looking at other
alternatives.

I looked at spidermonkey to embed in my c++ application but it seems a
little cumbersome dealing with C++ objects. Does anyone have any other
recommendations?

I do not know much on this area but some useful links are:
UnderC, a compact C++ interpreter:
http://home.mweb.co.za/sd/sdonovan/underc.html

Ch, an embeddable C/C++ interpreter for cross platform scripting,
numerical computing and 2D/3D plotting: http://www.softintegration.com

CINT, C/C++ interpreter: http://root.cern.ch/root/Cint.html

ROOT, Data Analysis Framework: http://root.cern.ch

Definitely you will find something here:

More C++ libraries: http://www.trumphurst.com/cpplibs/cpplibs.phtml


--
Ioannis Vranos

http://www23.brinkster.com/noicys

[Phlip]

fernandez.dan wrote:

I was wondering if anyone has any recommendation for
embbedding a script engine in a c++ application.
All of Lua, Python, Ruby, etc. are written with embedding in mind. Lua
hardly has any other presence.
I want to feed my C++
application scripts which based on the script would create C++ objects
and call the appropriate methods.

Here's a wrapper for Ruby's VALUE object:

class
rbValue
{
public:

rbValue(VALUE nuV = Qnil):
v(nuV)
{}

rbValue(char const * gv):
v(Qnil)
{
assert(gv);
assert('$' == gv[0]); // documentation sez this is optional. We
don't agree
v = rb_gv_get(gv);
}

operator VALUE() const { return v; }
rbValue &operator =(VALUE nuV) { v = nuV; return *this; }

rbValue
fetch(char const * tag)
{
return funcall("fetch", 2, rb_str_new2(tag), Qnil);
}

rbValue
fetch(int idx)
{
return funcall("fetch", 2, INT2FIX(idx), Qnil);
}

rbValue
fetch(size_t idx)
{
return funcall("fetch", 2, INT2FIX(idx), Qnil);
}

VALUE *
getPtr()
{
assert(T_ARRAY == TYPE(v));
return RARRAY(v)->ptr;
}

long
getLen()
{
assert(T_ARRAY == TYPE(v));
return RARRAY(v)->len;
}

rbValue
getAt(long idx)
{
assert(idx < getLen());
return RARRAY(v)->ptr[idx];
}
rbValue
operator[](long idx)
{
return getAt(idx);
}

bool isNil() { return Qnil == v; }

double to_f()
{
assert(T_FLOAT == TYPE(v) || T_FIXNUM == TYPE(v));
return NUM2DBL(v);
}

char const * to_s()
{
assert(T_STRING == TYPE(v));
return STR2CSTR(v);
}

rbValue
funcall (
char const * method,
int argc = 0,
VALUE arg1 = Qnil,
VALUE arg2 = Qnil,
VALUE arg3 = Qnil
)
{
return rb_funcall(v, rb_intern(method), argc, arg1, arg2, arg3);
}

rbValue
iv_get(char const * member)
{
VALUE iv = rb_iv_get(v, member);
return iv;
}

void
iv_set(char const * member, VALUE datum)
{
rb_iv_set(v, member, datum);
}

void
iv_set(char const * member, int datum)
{
iv_set(member, INT2FIX(datum));
}

private:
VALUE v;

}; // a smart wrapper for the Ruby VALUE type

Call its members like this:

void
push(rbValue xyzIn)
{
rbValue str = xyzIn.funcall("inspect");
OutputDebugStringA(str.to_s());
OutputDebugStringA("\n");
}

Google for that code to find its project.

--
Phlip
http://industrialxp.org/community/bi...UserInterfaces

[fernandez.dan]

Thanks for the input. I looked at Python and how it can be implemented
in a C++ by using SWIG. What do you think about Ruby? It is a pure
object oriented scripting language but I'm am newbie to that language.
I'm wondering if it is easier to access C++ objects over Python or
Javascript? Also looked at lua but it seems a bit old.

[Walter]

<fe***********@gmail.com> wrote in message
news:11**********************@o13g2000cwo.googlegr oups.com...

Hey I'm sorry if this is not the appropriate news group for this
question. I was wondering if anyone has any recommendation for
embbedding a script engine in a c++ application. I want to feed my C++
application scripts which based on the script would create C++ objects
and call the appropriate methods.

At the moment I created a simple interpreter within our C++ aplication
that we can feed our custom scripts. The interpreter is primitive and
it lacks alot of functionality that is why I am looking at other
alternatives.

I looked at spidermonkey to embed in my c++ application but it seems a
little cumbersome dealing with C++ objects. Does anyone have any other
recommendations?

DMDScript (a javascript implementation) can be embedded in C++ applications.
There's also a version for embedding in D programming language applications.

-Walter
www.digitalmars.com/dscript DMDScript

[Victor Bazarov]

fe***********@gmail.com wrote:

Thanks for the input. I looked at Python and how it can be implemented
in a C++ by using SWIG. What do you think about Ruby? It is a pure
object oriented scripting language but I'm am newbie to that language.
I'm wondering if it is easier to access C++ objects over Python or
Javascript? Also looked at lua but it seems a bit old.

Since I participated, I feel obliged to respond. I don't think about
Ruby, so the answer is "nothing". As to JavaScript (or should we call it
"LiveScript"?), I have also no idea what capabilities it provides. I know
that our products provide scriptability through Python and that there are
other possibilities. If there were a single scripting language that
covered all needs and satisfied all requirements, we wouldn't have such
a variety of choices. So, it's totally up to you to see which one suits
you. And let's not convert the short enumeration of a few options into
a full-blown discussion on scripting languages since it would be off-topic
here.

V

[Phlip]

fernandez.dan wrote:

Thanks for the input. I looked at Python and how it can be implemented
in a C++ by using SWIG.
You can also bond with Python using Boost, or using Python's raw C-style
API. SWIG is an elaborate adapter system to bond any object with any other
object in any language. We are not amused.
What do you think about Ruby?
It competes successfully with both Perl and Smalltalk, wisely leaving behind
the worst of both. My velocity using Ruby is triple that of any other
language.

Compare traversing a heterogeous list in Ruby to, say, Java:

myList.each { |node| node.virtualMethod() }

How many tokens would Java require to claw its way to the same (common)
result?
It is a pure
object oriented scripting language but I'm am newbie to that language.
I'm wondering if it is easier to access C++ objects over Python or
Javascript?
The "object" is relatively irrelevant. The point of objects is virtual
methods. If you have a binding layer then you have opaque methods anyway, so
they either dispatch or they don't. And otherwise "objects" are just
syntactic sugar.
Also looked at lua but it seems a bit old.

Lua is super-fast, and has block closures like Ruby. Its speed comes at the
price of a screwey object model that makes implementing objects
non-intuitive. And its speed makes it the leading contender for the
scripting layer for high-end video games.

Here's an oblique example of Lua driving a videogame:

http://flea.sourceforge.net/gameTestServer.pdf

And here's an example of Ruby in essentially the same role:

http://www.rubygarden.org/ruby?Fract...ine/FleaOpenGl

--
Phlip
http://industrialxp.org/community/bi...UserInterfaces

[Basil]

fe***********@gmail.com wrote in message news:<11**********************@o13g2000cwo.googleg roups.com>...

Hey I'm sorry if this is not the appropriate news group for this
question. I was wondering if anyone has any recommendation for
embbedding a script engine in a c++ application. I want to feed my C++
application scripts which based on the script would create C++ objects
and call the appropriate methods.

At the moment I created a simple interpreter within our C++ aplication
that we can feed our custom scripts. The interpreter is primitive and
it lacks alot of functionality that is why I am looking at other
alternatives.

I looked at spidermonkey to embed in my c++ application but it seems a
little cumbersome dealing with C++ objects. Does anyone have any other
recommendations?

Hello.

Open Basic this is realization of the interpreter of language Basic.

http://www.mktmk.narod.ru/eng/ob/ob.htm

Open Basic (OB) is realization of the interpreter of language Basic.
OB is developed for embed to user application as a script language.
User may attach (connect) user function to Open Basic execution
system.
The user functions can be written on C/C++, assembler or others
languages.
The user functions can receive parameters from the Basic-program and
return results to Basic-program.
Program interface of user functions allows determine type and order
of parameters at run-time.
OB realizes a subset of commands of language Basic.
OB it is written completely on C++ and it is realized as a class with
a name ob_obasic.
OB supports data of three types: floating point, signed integer, and
string and arrays of these types.
OB has multithread-safe code.

Now OB have library for GCC 3.2.2, BCB 6.0, MSVC 7.

For use OB need only one library for appropriated compiler and 6
header files:

mstore.h - policy
mvect.h - vector
mlist.h - list
mstack.h - stack
mhash.h - hash-table
ob.h - main header file of Open Basic
Open Basic have IDE for program debug.

Integrated development environment for Open Basic (IDE OB) is
intended for support of debugging programs of interpreter Open Basic.

http://www.mktmk.narod.ru/eng/ide_ob/ide_ob.htm

IDE OB can be an example for integration of interpreter Open Basic
for
OS Windows.

IDE OB is not a part of interpreter Open Basic.
Interpreter Open Basic can use without IDE OB.

IDE OB gives usual service of the debugging environment:
- Edit the text of programs
- Loading programs into interpreter (some modes)
- Start of program in the interpreter
- Stop program
- Step-by-step execution of program
- Animate execution of program
- Breakpoints (on interpreter level, do not support IDE OB)
- Viewing and updating variables ("Watch" window)
- Viewing diagnostic messages of the interpreter ("Messages" window)
- Support of operators PRINT and INPUT ("I/O Terminal" window)

IDE OB is written on Borland C++ Builder 6.0 (BCB 6.0).

Sincerely Yours
Basil

[Asfand Yar Qazi]

Phlip wrote:

What do you think about Ruby?

It competes successfully with both Perl and Smalltalk, wisely leaving behind
the worst of both. My velocity using Ruby is triple that of any other
language.

Compare traversing a heterogeous list in Ruby to, say, Java:

myList.each { |node| node.virtualMethod() }

How many tokens would Java require to claw its way to the same (common)
result?

I, too, now consider Ruby my scripting language of choice.
Integrating it with C++ needs the usual setjmp/longjmp exception
support hacks as with any other scripting languages that support
setjmp/longjmp exceptions. But the extensions API is probably the
best I've seen.

[Gernot Frisch]

<fe***********@gmail.com> schrieb im Newsbeitrag
news:11**********************@o13g2000cwo.googlegr oups.com...

Hey I'm sorry if this is not the appropriate news group for this
question. I was wondering if anyone has any recommendation for
embbedding a script engine in a c++ application. I want to feed my
C++
application scripts which based on the script would create C++
objects
and call the appropriate methods.

At the moment I created a simple interpreter within our C++
aplication
that we can feed our custom scripts. The interpreter is primitive
and
it lacks alot of functionality that is why I am looking at other
alternatives.

I looked at spidermonkey to embed in my c++ application but it seems
a
little cumbersome dealing with C++ objects. Does anyone have any
other
recommendations?

I've seen some guy, who wrote a script engine based on a gcc
installation shipped with the program. So, you just #inlcude
"my_plugin.h" and have all the interfaces ready, then click a "create
plugin" script that gcc's a .dll (or a .so on Linux/unix) - fast and
easy to implement. Very good idea I think. Especially for a game,
where performance is everything.
-Gernot

[Phlip]

Asfand Yar Qazi wrote:

I, too, now consider Ruby my scripting language of choice.
Integrating it with C++ needs the usual setjmp/longjmp exception
support hacks as with any other scripting languages that support
setjmp/longjmp exceptions. But the extensions API is probably the
best I've seen.

? I just use the 'protected' versions of functions.

I remain curious what happens to reality when you throw a C++ exception
from a C++ layer, thru the Ruby layer, and into a catch in the calling
C++ layer. Probably fireworks...

--
Phlip

[Ioannis Vranos]

Phlip wrote:

? I just use the 'protected' versions of functions.

I remain curious what happens to reality when you throw a C++ exception
from a C++ layer, thru the Ruby layer, and into a catch in the calling
C++ layer. Probably fireworks...

I think applause. :-)

--
Ioannis Vranos

http://www23.brinkster.com/noicys

[Owen Jacobson]

On Tue, 22 Mar 2005 00:51:22 +0000, Phlip wrote:

Compare traversing a heterogeous list in Ruby to, say, Java:

myList.each { |node| node.virtualMethod() }

How many tokens would Java require to claw its way to the same (common)
result?

This is so far off-topic that I can't even see C++ from here, but:

for (NodeType node : myList) {
node.virtualMethod ();
}

Looks like 15 tokens to me. Two more than the Ruby example. (Admittedly,
this is a new feature, and the idiom it replaces required far more tokens.)

HTH, Owen

[Phlip]

Owen Jacobson wrote:

This is so far off-topic that I can't even see C++ from here,
So what?
but:

for (NodeType node : myList) {
node.virtualMethod ();
}

Looks like 15 tokens to me. Two more than the Ruby example. (Admittedly, this is a new feature, and the idiom it replaces required far more

tokens.)

Props. And I know not to challenge Java, or its experimental
implementations, to show block closures, co-routines, generics, etc.

The important, topical goal here is understanding the friction between
static typing (like C++) and dynamic typing. The latter provides a
higher development velocity, at greater risk to your execution
velocity. We will see how Java can continue to compete.

--
Phlip

[Phlip]

> I think applause. :-)

Sour grapes, Ioannis?

--
Phlip
http://industrialxp.org/community/bi...UserInterfaces

[Yuriy Solodkyy]

If you targeting your application only for Windows platform, then you
can easily go with the scripting support provided by Windows. By
implementing a small COM object you'll get:

* Possibility of scripting in any language for which user registered a
scripting engine in the system (JScript and VBScript are there by
default and there is compatible scripting engine for Perl)
* Possibility to create and use inside the script any COM object with
dispatch interface registered in the system.
* Provide access to objects inside your application.
* Let user write event handlers for the events your objects have.

There was a nice article on CodeProject on how to embed Windows
scripting engine support into your application. Works great.

fe***********@gmail.com wrote:

Hey I'm sorry if this is not the appropriate news group for this
question. I was wondering if anyone has any recommendation for
embbedding a script engine in a c++ application. I want to feed my C++
application scripts which based on the script would create C++ objects
and call the appropriate methods.

At the moment I created a simple interpreter within our C++ aplication
that we can feed our custom scripts. The interpreter is primitive and
it lacks alot of functionality that is why I am looking at other
alternatives.

I looked at spidermonkey to embed in my c++ application but it seems a
little cumbersome dealing with C++ objects. Does anyone have any other
recommendations?