[Xotcl] NX objects and namespaces

[Gustaf Neumann]

Something in addition to Stefan's reply:

I have simplified your script to the version below. In essence

- statement 1:
    * an object "o1" (not fully qualified) is created in a namespace "ns1"
    * the fully qualified command name if "o1" is "::ns1::o1"

- statement 2:
- the object name "o1" is provided to property "pr"
- The property checks successfully, if "o1" exists as an object in "::ns1"
- The value of the property pr is still the string "o1".
- After setting this property, the constructor of class B is called.
- The constructor of B is executed in the global namespace "::"
- In the global namespace "o1" does not exist, therefore the
    error.

So, passing the object name fully qualified to "-pr" solves the
problem. I do agree, that the result is not fully satisfying
(the property was checked to be an object, but "suddenly"
it cannot be resolved). I might be possible in future versions
of nx to convert the passed in object name to a fully qualified
object name, but this has to be evaluated carefully.

I won't  be able to work on this in the next three weeks, but this is 
certainly
something to consider for future releases. ... For now, please pass
the fully qualified name

all the best

-gn


==========================================================================
nx::Class create A {
     :public method print {} {
         puts "[self] print"
     }
}

nx::Class create B {
     :property pr:object,required

     :method init {} {
         puts "i am in namespace [namespace current], the value of :pr '${:pr}' is command '[namespace which ${:pr}]'"
         ${:pr} print
     }
}

namespace eval ns1 {
     # statement 1
     A create o1

     # statement 2
     B create b1 -pr o1
}
==========================================================================



On 29.12.22 19:37, Maksym Zinchenko wrote:
> Hello, first of all Happy new year for all!
> I have a doubt about an object as a parameter and namespaces. For example I
> have 2 classes:
>
> package require nx
>> nx::Class create aClass {
>> : public method print {} {
>> puts "I'm an a object:  [[self] info name] ->  [[self] info parent] "
>> }
>> }
>>
>> nx::Class create bClass {
>> :property pr:object,required
>>
>> :method init {} {
>> puts "a_obj print result: "
>> ${:pr} print
>> }
>> }
>>
>> aClass create a_obj
>> bClass create b_obj -pr a_obj
>>
> It works the way it's supposed to work. Now inside the namespace:
>
> namespace eval testNameSpace {
>> aClass create a_obj1
>> a_obj1 print
>> bClass create b_obj1 -pr a_obj1
>> }
>>
> This will give me an error, because NX is trying to execute object passed
> as a parameter in global namespace:
>
> I'm an a object:  a_obj1 ->  ::testNameSpace
>> a_obj print result:
>> invalid command name "a_obj1"
>>
> My question is, I might be doing something wrong, what is the right way to
> do it? Or when I pass Object as parameter I need to add namespace manually,
> why it's not assuming [namespace current]?
>
> Thank you
> _______________________________________________
> Xotcl mailing list
> Xotcl at alice.wu.ac.at
> http://alice.wu.ac.at/mailman/listinfo/xotcl

-- 
Univ.Prof. Dr. Gustaf Neumann
Head of the Institute of Information Systems and New Media
of Vienna University of Economics and Business
Program Director of MSc "Information Systems"