diff options
Diffstat (limited to 'core/src/main/scala/mill/define/Applicative.scala')
| -rw-r--r-- | core/src/main/scala/mill/define/Applicative.scala | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/core/src/main/scala/mill/define/Applicative.scala b/core/src/main/scala/mill/define/Applicative.scala index 6d8ae3e2..686220f7 100644 --- a/core/src/main/scala/mill/define/Applicative.scala +++ b/core/src/main/scala/mill/define/Applicative.scala @@ -14,9 +14,16 @@ import scala.reflect.macros.blackbox.Context * Applier.zipMap(applyable1, applyable2){ (a1, a2, ctx) => ... a1 ... a2 ... } */ object Applicative { - trait Applyable[+T]{ + trait ApplyHandler[M[+_]]{ + def apply[T](t: M[T]): T + } + object ApplyHandler{ @compileTimeOnly("Target#apply() can only be used with a T{...} block") - def apply(): T = ??? + implicit def defaultApplyHandler[M[+_]]: ApplyHandler[M] = ??? + } + trait Applyable[M[+_], +T]{ + def self: M[T] + def apply()(implicit handler: ApplyHandler[M]): T = handler(self) } class ImplicitStub extends StaticAnnotation type Id[+T] = T @@ -64,7 +71,7 @@ object Applicative { def rec(t: Tree): Iterator[c.Tree] = Iterator(t) ++ t.children.flatMap(rec(_)) val bound = collection.mutable.Buffer.empty[(c.Tree, ValDef)] - val targetApplySym = typeOf[Applyable[_]].member(TermName("apply")) + val targetApplySym = typeOf[Applyable[Nothing, _]].member(TermName("apply")) // Derived from @olafurpg's // https://gist.github.com/olafurpg/596d62f87bf3360a29488b725fbc7608 @@ -75,7 +82,7 @@ object Applicative { c.internal.setInfo(ctxSym, weakTypeOf[Ctx]) val transformed = c.internal.typingTransform(t) { - case (t @ q"$fun.apply()", api) if t.symbol == targetApplySym => + case (t @ q"$fun.apply()($handler)", api) if t.symbol == targetApplySym => val localDefs = rec(fun).filter(_.isDef).map(_.symbol).toSet val banned = rec(t).filter(x => defs(x.symbol) && !localDefs(x.symbol)) |