Typeclass that contains string representation of a concrete type. This representation should correctly parse
and typecheck when used as a type in Scala source code.
Instances of TypeString are implicitly macro-materialized. The macro will fail if the type contains
references to local symbols, i.e. symbols that only exist in limited scope and cannot be referred to from
any place in source code. This includes type parameters, this-references to enclosing classes, etc.
because T is a local symbol that only has meaning inside its own method. However, if you provide external
TypeString instance for T, the macro will pick it up and no longer complain:
Typeclass that contains string representation of a concrete type. This representation should correctly parse and typecheck when used as a type in Scala source code.
Instances of
TypeStringare implicitly macro-materialized. The macro will fail if the type contains references to local symbols, i.e. symbols that only exist in limited scope and cannot be referred to from any place in source code. This includes type parameters, this-references to enclosing classes, etc.For example, the code below will NOT compile:
because
Tis a local symbol that only has meaning inside its own method. However, if you provide externalTypeStringinstance forT, the macro will pick it up and no longer complain:Then,
listTypeRepr[Int]will produce a string"List[Int]"