golang-samber-mo

Use mo.Option[string] for nullable columns instead of *string. Option implements sql.Scanner and driver.Valuer, so row.Scan and db.Exec work directly, and it also implements json.Marshaler so the same struct serves JSON responses.

Use Result[T] when one path is an error, such as a fallible operation. Use Either[L, R] when both outcomes are valid alternatives, like cached versus fresh data, since neither side implies failure.

Go methods cannot introduce new type parameters, so Option.Map returns Option[T] with the same type. For type-changing transforms like Option[int] to Option[string], use the curried option.Map function from the github.com/samber/mo/option sub-package.

No, keep (T, error) at public API boundaries for Go idiom compliance. Use Result internally for chaining multi-step pipelines, converting with TupleToResult at the start and extracting with Get at the end.

Future starts executing immediately upon construction, while Task is lazy and only runs when Run() is called. Task.Run() returns a *Future[T], making Task the right choice for deferred async computations.

Avoid monads for simple one-step operations where if err != nil is clearer, in performance-critical hot paths, and when zero values are semantically meaningful. Option adds value only when absence differs from the zero value.