Add abstract getter & setters for the redirect value.

source/redirect/base.ts

@@ -33,4 +33,8 @@ export abstract class Redirect<P extends RedirectParameters> {
   }
 
   public abstract redirect(url: URL | string): URL;
+
+  public abstract get redirectValue(): string;
+
+  public abstract set redirectValue(value: string);
 }

source/redirect/hostname.ts

@@ -11,4 +11,12 @@ export class HostnameRedirect extends Redirect<HostnameParameters> {
     redirected.hostname = this.parameters.hostname;
     return redirected;
   }
+
+  public get redirectValue(): string {
+    return this.parameters.hostname;
+  }
+
+  public set redirectValue(value: string) {
+    this.parameters.hostname = value;
+  }
 }

source/redirect/simple.ts

@@ -9,4 +9,12 @@ export class SimpleRedirect extends Redirect<SimpleParameters> {
   public redirect(): URL {
     return new URL(this.parameters.target);
   }
+
+  public get redirectValue(): string {
+    return this.parameters.target;
+  }
+
+  public set redirectValue(value: string) {
+    this.parameters.target = value;
+  }
 }