public static T?From(P p) { return(Convert <T, P> .From(p)); }
public static T?From(P?p) { return(p.HasValue? Convert <T, P> .From(p.Value): (T?)null); }
public static T?From(P p) { return(Convert <T, P> .From(p)); }
public static T?From(P?p) { return(p.HasValue? Convert <T, P> .From(p.Value): (T?)null); }