ID des modules de calcul : protection contre undefined

src/app/components/generic-calculator/calculator.component.ts

@@ -88,7 +88,11 @@ export class GenericCalculatorComponent extends BaseComponent implements OnInit,
     private formulaireService: FormulaireService;
 
     public get ID() {
-        return this._formulaire.uid;
+        if (this._formulaire) {
+            return this._formulaire.uid;
+        } else {
+            return "calculator_1";
+        }
     }
 
     constructor(