Chaining Effects in a Generator with Effect.forEach

// sendEmail : Mail => Promise<void>
// emailsSent() : () => void
const f = Effect.gen(function*() { 
  ...
  yield* Effect.forEach(mails: Array<Mail>, (m) =>
    pipe(
      Effect.promise(() => sendEmail(m)),
      Effect.tap(metrics.emailSent()),
    ),
  )
}