Function tx

packages/effect/src/Effect.ts:14528–14568

(
  effect: Effect<A, E, R>
)

 * @since 4.0.0
 */
export const tx = <A, E, R>(
  effect: Effect<A, E, R>
): Effect<A, E, Exclude<R, Transaction>> =>
  withFiber((fiber) => {
    let state = Context.getOrUndefined(fiber.context, Transaction)
    if (state) {
      return effect as Effect<A, E, Exclude<R, Transaction>>
    }
    // Create transaction state only at the outermost boundary
    state = { journal: new Map(), retry: false }
    let result: Exit.Exit<A, E> | undefined
    return uninterruptibleMask((restore) =>
      flatMap(
        whileLoop({
          while: () => !result,
          body: constant(
            restore(effect).pipe(
              provideService(Transaction, state),
              tapCause(() => {
                if (!state.retry) return void_
                return restore(awaitPendingTransaction(state))
              }),
              exit
            )
          ),
          step(exit: Exit.Exit<A, E>) {
            if (state.retry || !isTransactionConsistent(state)) {
              return clearTransaction(state)
            }
            if (Exit.isSuccess(exit)) {
              commitTransaction(fiber, state)
            } else {
              clearTransaction(state)
            }
            result = exit
          }
        }),
        () => result!
      )
    )
  })

const isTransactionConsistent = (state: Transaction["Service"]) => {
  for (const [ref, { version }] of state.journal) {