Booleans

Question

x = True
y = False
z = False
x or y and z == True.

Why is 'and' treated before 'or' ? Is this a python thing? Help me understand.

Answer 1

'and' is before 'or' in every programming language. There is an order of operations just like in math.

https://en.m.wikipedia.org/wiki/Order_of_operations#Programming_languages

Answer 2

arr = [1, True, 'a', 2]
print('a' in arr in arr)
Output is false. While:
print(('a': in arr) in arr)
Output is true

Schindlabua Henri Evjen Is python right to left without brackets for 'in' operations?

Answer 3

Even cooler: `and` is like multiplication and `or` is like addition in a pretty strict mathematical sense.

true behaves a bit like 1, false like 0:

true and true == true
1 * 1 == 1

false and true == false
0 * 1 == 0

false or false == false
0 + 0 == 0

false or true == true
0 + 1 == 1

(with 1+1 we have to squint a little to see it.)

And of course multiplication goes before addition :)

Answer 4

I don't write much python, but looks like it. Right-associativity is not terribly uncommon though. Think of `a ** b ** c`, or in other languages, `a ? b : c ? d : e` or `a = b = c`.

Answer 5

Thanks. Cool eye opener. *Not every programming language though. There are exceptions.