Previously in this post, I proposed a few macros to include custom coding path when conforming to Codable and have created a initial implementation. Now more features are added to the packages.
Now besides customizing coding path with @CodingField and ignoring fields with CodingIgnore, the following features are now supported:
- Transform the value before encoding and after decoding with
@CodingTransform,@DecodeTransformand@EncodeTransform - Validate the decoded value with
@CodingValidate - Provide settings for decoding sequence type with
@SequenceCodin  gField - Encode the whole instance by converting it into some single Codable value with
@SingleValueCodable - Encode Enums with
@EnumCodable.
For more information, please refer to the documentation
Examples:
@Codable
struct Person {
@CodingField("data", "id")
@DecodeTransform(source: String.self, with: { UUID(uuidString: $0)! })
@EncodeTransform(source: UUID.self, with: \.uuidString)
var id: UUID
@CodingField("data", "meta", "name")
@CodingValidate(source: String.self, with: { !$0.isEmpty })
@CodingValidate(source: String.self, with: { !$0.contains(where: { $0.isNumber }) })
var name: String
@CodingTransform(
.date.timeIntervalTransform(), // Date to TimeInterval (Double)
.double.multiRepresentationTransform(encodeTo: .string) // Double to String
)
var birthday: Date
@CodingIgnore
var habit: String = "writing Swift Macro"
@CodingField("data", "meta", "known_programming_languages")
@SequenceCodingField(
subPath: "name",
onMissing: .ignore,
onMismatch: .value("Swift"),
decodeTransform: Set.init
)
var knownProgrammingLanguages: Set<String>
}
@SingleValueCodable
struct FilePath {
@SingleValueCodableDelegate
var storage: String
var isDir: Bool = false
}
@EnumCodable(option: .adjacentKeyed())
enum Example {
@EnumCaseCoding(caseKey: "a_key", emptyPayloadOption: .emptyObject)
case a
@EnumCaseCoding(caseKey: "a_key", payload: .singleValue)
case b(Int)
@EnumCaseCoding(payload: .object(keys: "key1", "key2", "key3"))
case c(Int, label: String, _: Int)
}
And as before, the macros provide diagnostics in compile time for some errors.
