A basic filter that display a placeholder if the value is undefined or ""
{{ myValue | luifPlaceholder:"a fixed placeholder" }}
{{ myValue | luifPlaceholder: aVarInScope }}
MyValue : {{myValue}}
With fixed luifPlaceholder : {{ myValue | luifPlaceholder:"a fixed placeholder" }}
With dynamic luifPlaceholder : {{ myValue | luifPlaceholder:myPlaceholder }}