refactor: rename Serializing to Serializable and update README

Author: coenttb

README.md

@@ -91,13 +91,13 @@ let valid3 = try EmailAddress("\"user name\"@example.com")
 // Invalid addresses throw errors
 do {
     let invalid = try EmailAddress("no-at-sign")
-} catch EmailAddress.ValidationError.missingAtSign {
+} catch EmailAddress.Error.missingAtSign {
     print("Missing @ symbol")
 }
 
 do {
     let tooLong = try EmailAddress("verylonglocalpartthatexceedssixtyfourcharactersshouldnotbeallowed@example.com")
-} catch EmailAddress.ValidationError.localPartTooLong(let length) {
+} catch EmailAddress.Error.localPartTooLong(let length) {
     print("Local part too long: \(length) characters")
 }
 ```
@@ -148,7 +148,7 @@ let domain = try Domain("mail.example.com")
 ### Validation Errors
 
 ```swift
-public enum ValidationError: Error {
+public enum Error: Swift.Error {
     case missingAtSign
     case invalidDotAtom
     case invalidQuotedString

Sources/RFC 5321/RFC_5321.EmailAddress.Error.swift

@@ -34,7 +34,7 @@ extension RFC_5321.EmailAddress {
         case invalidLocalPart(_ error: LocalPart.Error)
 
         /// Domain validation failed
-        case invalidDomain(_ error: Domain.ValidationError)
+        case invalidDomain(_ error: RFC_1123.Domain.Error)
     }
 }
 

Sources/RFC 5321/RFC_5321.EmailAddress.swift

@@ -28,8 +28,12 @@ extension RFC_5321 {
         /// Initialize with validated components
         ///
         /// This is the canonical initializer. Components are already validated.
-        public init(displayName: (some StringProtocol)? = nil, localPart: LocalPart, domain: RFC_1123.Domain) throws(Error) {
-            self.displayName = displayName.map { String($0).trimming(.ascii.whitespaces) }
+        public init(
+            displayName: String? = nil,
+            localPart: LocalPart,
+            domain: RFC_1123.Domain
+        ) throws(Error) {
+            self.displayName = displayName?.trimming(.ascii.whitespaces)
             self.localPart = localPart
             self.domain = domain
 
@@ -89,10 +93,8 @@ extension RFC_5321.EmailAddress {
             let domain: RFC_1123.Domain
             do {
                 domain = try RFC_1123.Domain(domainString)
-            } catch let domainError as Domain.ValidationError {
+            } catch let domainError {
                 throw Error.invalidDomain(domainError)
-            } catch {
-                fatalError("Unexpected error type from RFC_1123.Domain.init: \(error)")
             }
 
             try self.init(
@@ -120,14 +122,12 @@ extension RFC_5321.EmailAddress {
             let domain: RFC_1123.Domain
             do {
                 domain = try RFC_1123.Domain(domainString)
-            } catch let domainError as Domain.ValidationError {
+            } catch let domainError {
                 throw Error.invalidDomain(domainError)
-            } catch {
-                fatalError("Unexpected error type from RFC_1123.Domain.init: \(error)")
             }
 
             try self.init(
-                displayName: nil as String?,
+                displayName: nil,
                 localPart: localPart,
                 domain: domain
             )
@@ -187,5 +187,5 @@ extension RFC_5321.EmailAddress: Codable {
 
 extension RFC_5321.EmailAddress: RawRepresentable {
     public var rawValue: String { String(self) }
-    public init?(rawValue: some StringProtocol) { try? self.init(rawValue) }
+    public init?(rawValue: String) { try? self.init(rawValue) }
 }

Sources/RFC 5321/exports.swift

@@ -5,4 +5,4 @@
 //  Created by Coen ten Thije Boonkkamp on 21/11/2025.
 //
 
-@_exported import struct RFC_1123.Domain
+@_exported import RFC_1123