lambda in for loop only takes last value [duplicate]

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Please read about minimal examples. Without reading your code, I believe you have run into a well known issue addressed in previous questions and answers that needs 2 lines to illustrate. Names in function bodies are evaluated when the function is executed.

funcs = [lambda: i for i in range(3)]
for f in funcs: print(f())

prints ‘2’ 3 times because the 3 functions are identical and the ‘i’ in each is not evaluated until the call, when i == 2. However,

funcs = [lambda i=i:i for i in range(3)]
for f in funcs: print(f())

makes three different functions, each with a different captured value, so 0, 1, and 2 are printed. In your statement

__cMenu.add_command(label="{}".format(option),
    command=lambda: self.filter_records(column, option))

add option=option before : to capture the different values of option. You might want to rewrite as

lambda opt=option: self.filter_records(column, opt)

to differentiate the loop variable from the function parameter. If column changed within the loop, it would need the same treatment.

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