Language decision: expression-bodied fn / getter does not return its value #60

fn double x to x mul 2 compiles to function double(x) { x * 2; } (no return), and get fn value to this.count to get value() { this.#count; }. The examples document this as "expression body (no return)" and require to return expr.

This is surprising for users coming from arrow-function style (x => x * 2) and silently produces undefined. The compiler could warn today.

Options

1. Keep the semantics, add a diagnostic/linter rule: "expression body has no effect, did you mean to return?" (non-breaking).
2. Make to expr return the expression (breaking change for code that relies on the statement form; needs a major version or an opt-in flag).
3. Introduce a distinct arrow-style form and leave to unchanged.

Needs a maintainer decision; option 1 can ship regardless.