Script objects

Script object looks like ordinary object. However, it's behaviour is described by small scripts - methods written in some scripting language.

They can be used for:

Custom application objects
Event and notiication handlers
Objects in servers with customisable behaviour
...

NOTE: See TODO list at the end of this page.

Using script objects

Just send it a message as to any other object:

[object sayHi];

Creating script objetcs

object = [STScriptObject scriptObject];
[object setEnvironment:someScriptingEnvironment];

Adding methods

Create a source:

source = @"sayHi Transcript showLine: 'Hi.'. ^self".

or

source = [NSString stringWithContentsOfFile:@"SomeFile"];

Get the the proper engine for a language used in the source:

engine = [STEngine engineForLanguageWithName:@"Smalltalk"];

create a method:

method = [engine methodFromSource:source
                      forReceiver:object
                    inEnvironment:Environment];

and finally add the method to the object:

   [object addMethod:method];

Methods with arguments

Well, no difference to any other methods. If you have source:

source = @"sayHiTo:someone Transcript showLine: ('Hi ', someone). ^self";

you can do:

[object sayHiTo:@"World"];

Script object interface

Script object understands following:

addMethod:aMethod
removeMethod:aMethod
removeMethodWithName:aString
methodWithName:aString
methodNames
respondsToSelector:aSelector

TODO

Here are unimplemented features of the Script Objects. Feel free to add them, if you have a bit of time. Please consult with the author of StepTalk and on the gnustep lists.

object variables (this is high priority)
inheritance of variables and methods (traits like in Self?)
object archiving
object cloning (copying)

integration with scripting contexts

script object builder application (it should be something simple)