How to use globals()[] within a class

Question

If I want to call upon a variable like so:

boolean_0 = True
boolean_1 = False
no = 0
while no < 2:
    if globals()[f'boolean_{no}']:
        print(f'Boolean {no}', 'is True')
    else:
        print(f'Boolean {no}', 'is False')
    no += 1

how could I do it if it were in a class like this?

class boolean_func():
    def __init__(self):
        self.boolean_0 = True
        self.boolean_1 = False

    def check_status(self):
        no = 0
        while no < 2:
            if globals()[f'boolean_{no}']:
                print(f'Boolean {no}', 'is True')
            else:
                print(f'Boolean {no}', 'is False')
            no += 1

Why do you think `globals` would work here? *There are no global variables with those names* — juanpa.arrivillaga, Sep 10 '21 at 03:48

score 2 · Accepted Answer · answered Sep 10 '21 at 02:41

Try using self.__dict__ instead:

class boolean_func():
    def __init__(self):
        self.boolean_0 = True
        self.boolean_1 = False

    def check_status(self):
        no = 0
        while no < 2:
            if self.__dict__[f'boolean_{no}']:
                print(f'Boolean {no}', 'is True')
            else:
                print(f'Boolean {no}', 'is False')
            no += 1
x = boolean_func()
x.check_status()

Output:

Boolean 0 is True
Boolean 1 is False

score 1 · Answer 2 · answered Sep 10 '21 at 02:46

Use getattr. Its the normal way to get attributes from objects and has the advantage that it works with class variables too.

class boolean_func():
    
    def __init__(self):
        self.boolean_0 = True
        self.boolean_1 = False
   
    def check_status(self):
        no = 0
        while no < 2:
            if getattr(self, f'boolean_{no}'):
                print(f'Boolean {no}', 'is True')
            else:
                print(f'Boolean {no}', 'is False')
            no += 1

boolean_func().check_status()

How to use globals()[] within a class

2 Answers2