E4006

This error occurs when the same local function name is declared multiple times within the same scope. Each local function name must be unique within its scope.

Erroneous Example

fn main {
  fn helper() {
    1 + 1
  }

  fn helper() { // E4006: local function 'helper' is already defined
    2 + 2
  }

  helper()
}

Suggestion

To fix this error, give each local function a unique name:

fn main {
  fn helper1() {
    1 + 1
  }

  fn helper2() {
    2 + 2
  }

  helper1()
  helper2()
}

You can also move one of the functions to a different scope or merge the functionality into a single function if they serve similar purposes.