As stated in the documentation, where
takes a function that returns a boolean value.
export interface DataArray<T> {
/** Filter the data array down to just elements which match the given predicate. */
where(predicate: (elem: T, index: number, arr: T[]) => boolean): DataArray<T>;
}
So this should work:
dv.pages("(1) Misc Notes/tasks").where(p => p.Completed != true && p.Status != 'Waiting' && p["Task Size"] != 'Large')