TypeAssigner

If tpe is a named type, return the type with those alternatives as denotations which are accessible (or NoType, if no alternatives are accessible).

Also performs the following normalizations on the type tpe. (1) if the owner of the denotation is a package object, it is assured that the package object shows up as the prefix. (2) in Java compilation units, Object is replaced by defn.FromJavaObjectType

Assign type of RefinedType. Refinements are typed as if they were members of refinement class refineCls.

Type assignment method. Each method takes as parameters

• an untpd.Tree to which it assigns a type,
• typed child trees it needs to access to cpmpute that type,
• any further information it needs to access to compute that type.

Try to make tpe accessible, emit error if not possible

Return a potentially skolemized version of qualTpe to be used as a prefix when selecting name.

The qualifying class of a this or super with prefix qual (which might be empty).

A denotation exists really if it exists and does not point to a stale symbol.

Substitute argument type argType for parameter pref in type tp, skolemizing the argument type if it is not stable and pref occurs in tp.

Substitute types of all arguments args for corresponding params in tp. The number of parameters params may exceed the number of arguments. In this case, only the common prefix is substituted.

The type of the selection tree, where qual1 is the typed qualifier part.

Normalize type T appearing in a new T by following eta expansions to avoid higher-kinded types.