FUCKING typescript

doesnt-work.ts

// Errors on line 12
// Operator '!==' cannot be applied to types 'boolean' and 'View'.
class Server {
    currentView: View;

    manualView: ManualView;

    private showViewCommand(view: View, data?: string) {
        let oldView = this.currentView;
        this.currentView = view;

        if( !this.currentView !== oldView ){
            this.manualView.onLoad();
        }
    }
}

stupid-objects.ts

// Errors on line 12
// Property 'data' does not exist on type '{}'.
class MyClass {
    constructor(data?: MyInterface) {
        this.model = {
            data: {
                someProp: true
            }
        };

        if( data ){
            this.model.data = data;
        }
    }
}

stupid-properties.ts

// Property 'contentWindow' does not exist on type 'Element'.
document.querySelector( 'iframe' ).contentWindow.postMessage(command, '*');

// "Proper" way to do it
(<HTMLIFrameElement>document.querySelector( 'iframe' )).contentWindow.postMessage(command, '*');