changes and optimisations

src/app/pipes/lang-route.pipe.ts

@@ -7,19 +7,30 @@ import { LanguageService } from '../services/language.service';
 })
 export class LangRoutePipe implements PipeTransform {
   private langService = inject(LanguageService);
+  private lastLang = '';
+  private lastInput: unknown = null;
+  private lastResult: string | (string | number)[] = '';
 
   transform(value: string | (string | number)[]): string | (string | number)[] {
     const lang = this.langService.currentLanguage();
 
+    // Short-circuit if nothing changed
+    if (lang === this.lastLang && value === this.lastInput) {
+      return this.lastResult;
+    }
+
+    this.lastLang = lang;
+    this.lastInput = value;
+
     if (typeof value === 'string') {
-      return value === '/' ? `/${lang}` : `/${lang}${value}`;
-    }
-
-    if (Array.isArray(value) && value.length > 0) {
+      this.lastResult = value === '/' ? `/${lang}` : `/${lang}${value}`;
+    } else if (Array.isArray(value) && value.length > 0) {
       const [first, ...rest] = value;
-      return [`/${lang}${first}`, ...rest];
+      this.lastResult = [`/${lang}${first}`, ...rest];
+    } else {
+      this.lastResult = value;
     }
 
-    return value;
+    return this.lastResult;
   }
 }