Error Handling

throw accepts any value, but Error objects provide names, messages, stacks, and causes. Throw specific errors at clear contract boundaries.

Preserve context

function parseConfig(text) {
  try {
    return JSON.parse(text);
  } catch (error) {
    throw new SyntaxError("Invalid configuration", { cause: error });
  } finally {
    // unconditional follow-up, not usually return
  }
}

Catch only when you can recover, add context, or report at a boundary. Avoid swallowing errors or returning from finally. Custom Error subclasses can carry stable codes. Promise rejections require awaited try/catch or chain rejection handlers; global unhandled hooks are last-resort reporting, not normal recovery.