unnecessary_statements

Unnecessary statement.

The analyzer produces this diagnostic when an expression statement has no clear effect.

The following code produces this diagnostic because the addition of the returned values from the two invocations has no clear effect:

void f(int Function() first, int Function() second) {
  first() + second();
}

If the expression doesn't need to be computed, then remove it:

void f(int Function() first, int Function() second) {
}

If the value of the expression is needed, then make use of it, possibly assigning it to a local variable first:

void f(int Function() first, int Function() second) {
  print(first() + second());
}

If portions of the expression need to be executed, then remove the unnecessary portions:

void f(int Function() first, int Function() second) {
  first();
  second();
}

Unless stated otherwise, the documentation on this site reflects Dart 3.8.0. Page last updated on 2025-05-08. View source or report an issue.