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// SPDX-FileCopyrightText: 2025 Stefan Majewsky <majewsky@gmx.net>
// SPDX-License-Identifier: Apache-2.0
package refined
// A private type that appears in interfaces to make them unimplementable for types outside this package.
type seal struct{}
// This interface is currently only implemented by Scalar[S, V].
// But by having this interface as an intermediate, New() and Literal() can
// work with other classes of refinement types in the future.
type isARefinementType[S any, V any] interface {
refinedSeal() seal
refinedNew(V) (S, error)
}
// This interface is currently only implemented by Scalar[S, V].
// But by having this interface as an intermediate, ValidateUnmarshaled() can
// work with other classes of refinement types in the future.
//
// Because of how the reflection logic in ValidateUnmarshaled() is written,
// this interface is restricted to not have any type parameters.
type validationTarget interface {
refinedSeal() seal
IsValid() bool
}
// New checks if the provided value is acceptable for the refinement type S,
// and returns an instance of S if so, or an error if not.
// For example, given a refinement type like:
//
// type AccountName struct {
// refined.Scalar[AccountName, string]
// }
// // not shown: implementation of refined.IsAScalar[AccountName, string] interface on AccountName
//
// An instance of this refinement type can be constructed like so:
//
// var userInput string
// accountName, err := refined.New[AccountName](userInput)
func New[S isARefinementType[S, V], V any](value V) (S, error) {
var empty S
return empty.refinedNew(value)
}
// Literal is like New, but panics on error.
// This function is intended for dealing with literal values, where unexpected errors are not possible.
// For example:
//
// receiverName, err := refined.New[NonEmptyString]("Beitragsservice")
// handle(err)
// postCode, err := refined.New[PostCode](50616)
// handle(err)
// town, err := refined.New[NonEmptyString]("Cologne")
// handle(err)
// testAddress := Address {
// ReceiverName: receiverName,
// PostCode: postCode,
// Town: town,
// }
//
// can be shortened to:
//
// testAddress := Address {
// ReceiverName: refined.Literal[NonEmptyString]("Beitragsservice"),
// PostCode: refined.Literal[PostCode](50616),
// Town: refined.Literal[NonEmptyString]("Cologne"),
// }
func Literal[S isARefinementType[S, V], V any](value V) S {
var empty S
s, err := empty.refinedNew(value)
if err != nil {
panic(err.Error())
}
return s
}
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