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Unforgivable! It's difficult to explain how could I forget it!

The line 08 should be replaced from "class.child()", a simple class, to "class.child(parent)", subclass inheriting attributes and methods of "parent".

But, despite this mistake, the problem related in the previous message is still occuring with the same exact diagnosis!

On 05-01-2011 21:23, Norbert Kiesel wrote:

On Wed, 2011-01-05 at 21:03 -0200, Luciano de Souza wrote:

Hi all,

I was trying to create a graphical interface using IUP with object
oriented programming. Something wrong occurs. I prefer to simplify the
example to ilustrate what is happining.

In the original code, the class "parent" defines the window general
behavior and the child class is a form inheriting methods and
attributes. I prefer to simplify because the quantity of code.

But the problem is the same: how to access in child class an attribute
created in the parent?

the result of 14th line is "nil", whereas I expected 15 as the answer. I
tried self.a in the place of parent.a, but the result is still "nil". I
tried to declare in the 5th line "parent.a", but the result is the same.

01 require('classlib')
03 class.parent()
04 function parent:__init()
05 self.a = 15
06 end
08 class.child()
09 function child:__init()
10 self.b = 22
11 end
13 function child:display()
14 print(parent.a)
15 print(self.b)
16 end
18 x = child()
19 x:display()
Barring any black magic in classlib: where is defined that child is a
subclass of parent?