Python Forum

Hi. I've got a problem with exec() function in my class. If code is like:

    def rysuj(self, frame, tuptus):
        for bu in tuptus:
            def foo():
                print(self.x_coord)
                exec('self.'+'y_coord')
            foo()

everything is fine, but if i delate print:

    def rysuj(self, frame, tuptus): 
        for bu in tuptus:
            def foo():
                exec('self.'+'y_coord')
            foo()

gives me an error

Error:
"C:\Users\karol\anaconda3\envs\porjekt ostateczny\python.exe" "C:\Users\karol\PycharmProjects\porjekt ostateczny\main_menu_by_tkinter_2.py"
Exception in Tkinter callback
Traceback (most recent call last):
  File "C:\Users\karol\anaconda3\envs\porjekt ostateczny\lib\tkinter\__init__.py", line 1705, in __call__
    return self.func(*args)
  File "C:\Users\karol\PycharmProjects\porjekt ostateczny\main_menu_by_tkinter_2.py", line 152, in <lambda>
    command=lambda: self.rysuj(self.ctr_left,przyciski_rysuj),
  File "C:\Users\karol\PycharmProjects\porjekt ostateczny\main_menu_by_tkinter_2.py", line 177, in rysuj
    foo()
  File "C:\Users\karol\PycharmProjects\porjekt ostateczny\main_menu_by_tkinter_2.py", line 176, in foo
    exec('self.'+'y_coord')
  File "<string>", line 1, in <module>
NameError: name 'self' is not defined

does anybody know why?

Pass 'self' as parameter.

def rysuj(self, frame, tuptus): 
    for bu in tuptus:
        def foo(self):
            exec('self.'+'y_coord')
        foo(self)
   

So why it works with 'print(self.x_coord)'?

Because print function set te locals variables. See below:

def rysuj(self, frame, tuptus): 
    for bu in tuptus:
        def foo():
            print(locals())
            exec('self.'+'y_coord')
        foo()

and

def rysuj(self, frame, tuptus): 
    for bu in tuptus:
        def foo():
            print(self)
            print(locals())
            exec('self.'+'y_coord')
        foo()

I get it :D Thank you

why would you have something like this in the class in the first place?

I tried to use similar way to pack buttons with command in function. I used closure instead.