Optimize Email Regex

Code/Light.GuardClauses/RegularExpressions.cs

@@ -5,15 +5,30 @@ namespace Light.GuardClauses;
 /// <summary>
 /// Provides regular expressions that are used in string assertions.
 /// </summary>
+#if NET8_0
+public static partial class RegularExpressions
+#else
 public static class RegularExpressions
+#endif
 {
+    /// <summary>
+    /// Gets the string that represents the <see cref="EmailRegex" />.
+    /// </summary>
+    public const string EmailRegexText =
+        @"^[\w!#$%&'*+\-/=?\^_`{|}~]+(\.[\w!#$%&'*+\-/=?\^_`{|}~]+)*@((((\w+\-?)+\.)+[a-zA-Z]{2,4})|(([0-9]{1,3}\.){3}[0-9]{1,3}))$";
+
     /// <summary>
     /// Gets the default regular expression for email validation.
     /// This pattern is based on https://www.rhyous.com/2010/06/15/csharp-email-regular-expression/ and
     /// was modified to satisfy all tests of https://blogs.msdn.microsoft.com/testing123/2009/02/06/email-address-test-cases/.
     /// </summary>
-    public static readonly Regex EmailRegex = new (
-        @"^[\w!#$%&'*+\-/=?\^_`{|}~]+(\.[\w!#$%&'*+\-/=?\^_`{|}~]+)*@((((\w+\-?)+\.)+[a-zA-Z]{2,4})|(([0-9]{1,3}\.){3}[0-9]{1,3}))$",
-        RegexOptions.CultureInvariant | RegexOptions.ECMAScript
-    );
+    public static readonly Regex EmailRegex =
+#if NET8_0
+        GenerateEmailRegex();
+
+    [GeneratedRegex(EmailRegexText, RegexOptions.ECMAScript | RegexOptions.CultureInvariant)]
+    private static partial Regex GenerateEmailRegex();
+#else
+        new (EmailRegexText, RegexOptions.ECMAScript | RegexOptions.CultureInvariant | RegexOptions.Compiled);
+#endif
 }