Re: A TclOO question

Helmut Giese <hgiese@ratiosoft.com> wrote:

Hello out  there,
say I have a class and 2 instances like so
 
oo::class create MyClass {
    constructor {someVal} {
        my variable myVar
        set myVar $someVal
    }
    method get {} {
        my variable myVar
       return $myVar
   }
    method set {val} {
        my variable myVar
        set myVar $val
    }
}
 
MyClass create obj1 33
MyClass create obj2 99
 
How can I set a trace on 'myVar' of 'obj2'? 
I found an example on the doc of the 'my' command but it sets a trace
on a global variable during which an object is invoked - which doesn't
fit my situation
Any help will be greatly appreciated
Helmut

From outside the object, one way is, after you create the objects:

Get the object's namespace:

% info object namespace obj2
::oo::Obj13

Then infer the location of the variable:

% set ::oo::Obj13::myVar
99

Setting a trace on ::oo::Obj13::myVar should be trivial now.

From inside one of the object's methods, the 'my varname' gives you the
full namespace name:

    oo::class create MyClass {
        constructor {someVal} {
            my variable myVar
            set myVar $someVal
        }
        method where {} {
          puts "myVar is at [my varname myVar]"
        }
    }
    ::MyClass
    % MyClass create obj1 33
    ::obj1
    % obj1 where
    myVar is at ::oo::Obj12::myVar
    %