E4200

Compiler diagnostic name: struct_constr_incorrect_return_type.

A struct constructor must return the struct type itself. If the constructor signature returns another type, the declaration cannot be used as that struct’s constructor.

Erroneous example

///|
priv struct Point {
  x : Int
}

///|
fn Point::Point(_: Int) -> String {
  ""
}

Suggestion

Make the constructor return the struct type and implement the matching Type::Type function.

///|
priv struct Point {
  x : Int
}

///|
fn Point::Point(x : Int) -> Point {
  { x, }
}

///|
test {
  let point = Point(1)
  inspect(point.x, content="1")
}