Type aliases

A namespace type declaration aliases another type:

public type PlayerId = Int64
private type Scores = {[String]: Int}

The alias follows normal namespace visibility. It can appear in signatures, local annotations, and nested type expressions:

public function increase(id: PlayerId, scores: Scores): PlayerId
    return id + 1
end

An alias erases recursively to its target before HIR. It has exactly the target’s operations, layout, conversions, and runtime identity. It is not a nominal wrapper and adds no constructor.

Alias chains are allowed:

private type Score = Int
private type ScoreList = {Score}

Direct and indirect cycles are rejected. The initial rc.3 alias form has no type parameters, so Score<String> and type Box<T> = ... are not supported.