20250206 関数型DDD 4

Transcript

1. ؔ਺ܕଓ͖
2. લճ
3. type Option<'a> = | Some of 'a | None
4. type Result<'Success, 'Failure> = | Ok of 'Success | Error of 'Failure
5. ܕʹΑΔ υϝΠϯϞσϦϯά
6. ܕΛίʔυԽ
7. // ----- ະݕূͷঢ়ଶ ----- data UnvalidatedOrder = UnvalidatedCustomerInfo AND UnvalidatedShippingAddress AND UnvalidatedBillingAddress AND list of UnvalidatedOrderLine
8. work f low "Place Order" = input: UnvalidatedOrder output (on success): OrderAcknowledgmentSent AND OrderPlaced (to send to shipping) AND BillableOrderPlaced (to send to billing) output (on error): InvalidOrder
9. جຊతͳߟ͑
10. // ܕΛఆٛ type CustomerId = CustomerId of int type OrderId = OrderId of int // ஋Λఆٛ let customerId = CustomerId 42 let orderId = OrderId 42 // CustomerIdΛ࢖͏ؔ਺Λఆٛ let processCustomerId (id: CustomerId) = ... // OrderIdΛ౉͢ͱ -- ίϯύΠϥʔΤϥʔʂ processCustomerId orderId
13. ϫʔΫϑϩʔ
14. type ValidateOrder = UnvalidatedOrder -> ValidatedOrder
15. ग़ྗ΍ೖྗ͕ෳࡶͳ৔߹
16. ೖग़ྗ͕ෳ਺
17. type PlaceOrderEvents = { AcknowledgmentSent : AcknowledgmentSent OrderPlaced : OrderPlaced BillableOrderPlaced : BillableOrderPlaced } type PlaceOrder = UnvalidatedOrder -> PlaceOrderEvents
18. ೖग़ྗ͕Ͳ͔ͬͪ
19. type CategorizedMail = | Quote of QuoteForm | Order of OrderForm // etc type CategorizeInboundMail = EnvelopeContents -> CategorizedMail
20. ΤϥʔΛฦ͢Մೳੑ
21. type ValidateOrder = UnvalidatedOrder -> ValidatedOrder type ValidateOrder = (unvalidatedOrder: UnvalidatedOrder) => ValidatedOrder;
22. type ValidateOrder = UnvalidatedOrder -> Result<ValidatedOrder, ValidationError list> and ValidationError = { FieldName : string ErrorDescription : string }
23. ͞Βʹඇಉظ
24. type ValidationResponse<'a> = Async<Result<'a, ValidationError list>> type ValidateOrder = UnvalidatedOrder -> Async<Result<ValidatedOrder, ValidationError list>> type ValidateOrder = UnvalidatedOrder -> ValidationResponse<ValidatedOrder>