E4199

Compiler diagnostic name: struct_has_no_constr.

The call syntax Type(...) is available only for structs that declare a constructor. A regular record-style struct can still be created with a record literal, but it does not automatically get a constructor function with the struct name.

Erroneous example

///|
pub(all) struct Point {
  x : Int
}

///|
test {
  let _ : Point = Point(1)
}

Suggestion

Use record construction, or declare and implement a constructor before calling the struct as a function.

///|
pub(all) struct Point {
  x : Int
}

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

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