global-statement (PLW0603)

Added in v0.0.253 · Related issues · View source

Derived from the Pylint linter.

What it does

Checks for the use of global statements to update identifiers.

Why is this bad?

Pylint discourages the use of global variables as global mutable state is a common source of bugs and confusing behavior.

Example

var = 1


def foo():
    global var  # [global-statement]
    var = 10
    print(var)


foo()
print(var)

Use instead:

var = 1


def foo():
    var = 10
    print(var)
    return var


var = foo()
print(var)