Similar to task macros, the parsed value is accessed by calling `parsed`
on a Parser[T], Initialize[Parser[T]], or Initialize[State => Parser[T]].
Values of tasks and settings may be accessed as usual via `value`.
In order to correctly pattern match Tree subclasses in reflection/macros,
scalac needs the corresponding implicit for *Tag available because the types
are only abstract types.
That is, implement Initialize[Task[T]].flatten correctly.
This requires preserving the transformations applied in a scope so that
they can be applied to an Initialize value after static settings have been
evaluated.
* use normal TypeTree constructor
* remove unnecessary 'with Singleton' in macro utility
* integrate changes suggested by @xeno-by
* add refVar back and call asTypeConstructor instead of asType to refer to a type variable
1. KList[M[_]] now instead of KList[HL <: HList, M[_]]
a. head, tail work properly in this variant
b. disadvantage is that full type not easily transformed to new type constructor
2. AList abstracts on K[L[x]], a higher order type constructor.
A. Instances written for:
a. KList
b. Seq[M[T]] for a fixed T
c. TupleN
d. single values
e. operate on one type constructor when nested
B. Main disadvantage is type inference. It just doesn't happen for K[L[x]].
This is mitigated by AList being used internally and rarely needing to construct a K.
* split several source files
* move base settings sources (Scope, Structure, ...) into main/settings/
* breaks cycles. In particular, setting system moved from Project to Def
Mark Harrah