Skip to main content

move-variable-outside-iteration

added in: 1.13.0
warning
🛠
Pro+

Warns when a variable does not depend on the outer loop and can be moved out.

This rule helps avoid unnecessary declarations of variables that can be declared only once.

❌ Bad:

void fn() {
  final list = [1, 2, 3];

  for (final element in list) {
    final reversed = list.reversed; // LINT: This variable does not depend on the loop variables. Try moving the variable out.

    ...
  }
}

✅ Good:

void fn() {
  final list = [1, 2, 3];
  final reversed = list.reversed; // Correct, calculated only once

  for (final element in list) {
    ...
  }
}