This covers the case described in #1361 plus an esoteric case too.
Parsers are initialized when sbt starts and text completions use the
knowledge at that time. If we happen to move a new file that should
influence the behaviour of the tab completion, that file will not be
picked up. Before, since we were throwing an error, the previous case
that would no produce any tab completion would also fail, though the
files are legitimately in the correct place.
We don't have to care about migrations in these removals because no one
should be depending on these methods directly. People consume scripted
via the sbt plugin.
This commit also removes the unused `CompatibilityLevel` which is
completely outdated, making reference to Scala 2.9 et al.
This was already supported in the internal Scripted used by sbt but not
in the ScriptedPlugin. This is fixed by just copy-pasting the modified
parser. We will have to wait for sbt itself to be built using an sbt
with the upgraded ScriptedPlugin to be able to avoid the code duplication.
All of `sbtVersion`, `defScalaVersion` and `buildScalaVersions` were
not used anymore. According to @harrah they are coming from really
old days of sbt and are not needed because of changes to how sbt
interacts with different Scala versions.
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`.
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.