Fix a compilation & made refactoring

Author: eleev

Sources/SwiftBoost/Foundation/Extensions/LocaleExtension.swift

@@ -12,19 +12,29 @@ public extension Locale {
     }
 
     func localised(in locale: Locale) -> String? {
-        guard let currentLanguageCode = {
-            if #available(iOS 16, *) {
-                return self.language.languageCode?.identifier
-            } else {
-                return self.languageCode
-            }
-        }() else { return nil }
-        guard let toLanguageCode = {
-            if #available(iOS 16, *) {
+        /**
+         Returns the identifier for the language code of the given `Locale`.
+
+         This method checks for the availability of specific APIs introduced in iOS 16.0 and macOS 13.0 versions or later. If these APIs are available, it returns the `identifier` property of the `languageCode` from the `Locale`. Otherwise, it uses the `languageCode` property directly from the `Locale`.
+
+         - Parameter locale: The `Locale` for which the language code identifier is required.
+
+         - Returns: The language code identifier of the given `Locale`. If the specific APIs are unavailable (i.e., the device's OS version is older than iOS 16.0 or macOS 13.0), it returns the language code directly.
+         */
+        func supportedLangCodeId(for locale: Locale) -> String? {
+            //  Checks for the availability of specific APIs introduced in iOS 16.0 and macOS 13.0 versions or later.
+            if #available(iOS 16.0, macOS 13.0, *) {
                 return locale.language.languageCode?.identifier
             } else {
                 return locale.languageCode
             }
+        }
+        
+        guard let currentLanguageCode = {
+            supportedLangCodeId(for: self)
+        }() else { return nil }
+        guard let toLanguageCode = {
+            supportedLangCodeId(for: locale)
         }() else { return nil }
         let nslocale = NSLocale(localeIdentifier: toLanguageCode)
         let text = nslocale.displayName(forKey: NSLocale.Key.identifier, value: currentLanguageCode)