Julia Variable value reset

Question

I'm just starting in Julia after a strong background in C++. I'm having an issue with my integer variables being reset to what I initialized them as in the beginning of my program.. even though I changed the variable value inside a function. Can anyone explain why this is?

num = 0

function getNum()
    num = 1
end

getNum()
num    #this returns 0, not 1

This is a problem because I will need to reference that variable in another function.

Answer 1

num is in global scope (note that the same behavior applies in e.g. Python)

If necessary, you could modify it by referencing as a global:

function getNum()
   global num = 1
end

However, it is worth considering whether there is a more effective way to structure your code. Global variables can be useful in some situations, but they can also make code more difficult to reason about.