Unify constructor

src/logger.ts

@@ -7,11 +7,9 @@ export let options: Options = {
 }
 
 export class Logger {
-    private readonly _namespace: string
-
-    constructor(namespace: string) {
-        this._namespace = namespace
-    }
+    constructor(
+        private readonly _namespace: string
+    ) {}
 
     public get namespace() : string {
         return this._namespace