ERROR in src/app/services/navigation.service.ts:38:16 - error TS1015: Parameter cannot have question mark and initializer.

38   startLoading(loaderMessage?: string = undefined) {
                  ~~~~~~~~~~~~~
src/app/services/navigation.service.ts:42:32 - error TS2339: Property 'loaderMessage' does not exist on type '{ message: string; }'.

42     if (loaderMessage) message.loaderMessage = loaderMessage;
                                  ~~~~~~~~~~~~~
src/app/services/alert.service.ts:23:13 - error TS2339: Property 'alertType' does not exist on type '{}'.

23     message.alertType = 'error';
               ~~~~~~~~~
src/app/services/alert.service.ts:24:13 - error TS2339: Property 'alertCloseMessage' does not exist on type '{}'.

24     message.alertCloseMessage = 'Ricarica la pagina';
               ~~~~~~~~~~~~~~~~~
src/app/services/alert.service.ts:25:13 - error TS2339: Property 'alertMessage' does not exist on type '{}'.

25     message.alertMessage = alertMessage;
               ~~~~~~~~~~~~
src/app/services/alert.service.ts:26:13 - error TS2339: Property 'alertCloseable' does not exist on type '{}'.

26     message.alertCloseable = false;
               ~~~~~~~~~~~~~~
src/app/services/alert.service.ts:28:15 - error TS2339: Property 'alertActions' does not exist on type '{}'.

28       message.alertActions.push(callback);
                 ~~~~~~~~~~~~
src/app/services/alert.service.ts:35:13 - error TS2339: Property 'alertType' does not exist on type '{}'.

35     message.alertType = 'success';
               ~~~~~~~~~
src/app/services/alert.service.ts:36:13 - error TS2339: Property 'alertCloseMessage' does not exist on type '{}'.

36     message.alertCloseMessage = 'Torna al listato';
               ~~~~~~~~~~~~~~~~~
src/app/services/alert.service.ts:37:13 - error TS2339: Property 'alertMessage' does not exist on type '{}'.

37     message.alertMessage = alertMessage;
               ~~~~~~~~~~~~
src/app/services/alert.service.ts:38:13 - error TS2339: Property 'alertCloseable' does not exist on type '{}'.

38     message.alertCloseable = false;
               ~~~~~~~~~~~~~~
src/app/services/alert.service.ts:40:15 - error TS2339: Property 'alertActions' does not exist on type '{}'.

40       message.alertActions.push(callback);
                 ~~~~~~~~~~~~

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