Give a more helpful error message when using 'Type.propertyName' as a qualified type.

[DanielRosenwasser]

https://twitter.com/KrisJordan/status/890594965541269505

[osi-oswald]

What was the reason to disallow qualified names? It feels more natural to be able to use both ways to look up member types.

[RyanCavanaugh]

This code has always been legal:

interface Person { name: string; }
namespace Person {
  export type name = number;
}
var x: Person.name;

We didn't want to make a breaking change to make it illegal, or change the meaning of this code

[osi-oswald]

I see, but I guess this kind of ambiguity is quite rare (at least nowadays)? Could the following be a valid workaround:

• Allow qualified names for interfaces/classes
• If there is an ambiguity, namespaces take precedence (to not break existing code)