Prefer SAMs whenever possible

core/shared/src/main/scala/reftree/core/RefTree.scala

@@ -133,9 +133,7 @@ trait ToRefTree[A] { self =>
 object ToRefTree extends CollectionInstances with HackedCollectionInstances with GenericInstances {
 
   /** A shorthand method for creating [[ToRefTree]] instances */
-  def apply[A](toRefTree: A => RefTree): ToRefTree[A] = new ToRefTree[A] {
-    def refTree(value: A) = toRefTree(value)
-  }
+  def apply[A](toRefTree: A => RefTree): ToRefTree[A] = (value: A) => toRefTree(value)
 
   def const[A](refTree: => RefTree): ToRefTree[A] =
     (_: A) => refTree

core/shared/src/main/scala/reftree/geometry/Interpolation.scala

@@ -49,9 +49,7 @@ trait SemiInterpolation[A] { self =>
 }
 
 object SemiInterpolation {
-  def apply[A](f: (A, Double) => A): SemiInterpolation[A] = new SemiInterpolation[A] {
-    def apply(value: A, t: Double) = f(value, t)
-  }
+  def apply[A](f: (A, Double) => A): SemiInterpolation[A] = (value: A, t: Double) => f(value, t)
 }
 
 /**
@@ -213,9 +211,8 @@ trait Interpolation[A] { self =>
 
 object Interpolation {
   /** A shorthand for constructing interpolations */
-  def apply[A](f: (A, A, Double) => A): Interpolation[A] = new Interpolation[A] {
-    def apply(left: A, right: A, t: Double): A = f(left, right, t)
-  }
+  def apply[A](f: (A, A, Double) => A): Interpolation[A] =
+    (left: A, right: A, t: Double) => f(left, right, t)
 
   /** A basic linear interpolation for doubles */
   val double = Interpolation[Double]((l, r, t) => l * (1 - t) + r * t)

core/shared/src/main/scala/reftree/geometry/Point.scala

@@ -12,9 +12,7 @@ trait Translatable[A] {
 }
 
 object Translatable {
-  def apply[A](f: (A, Point) => A): Translatable[A] = new Translatable[A] {
-    def translate(value: A, delta: Point) = f(value, delta)
-  }
+  def apply[A](f: (A, Point) => A): Translatable[A] = (value: A, delta: Point) => f(value, delta)
 
   implicit def `List Translatable`[A](implicit t: Translatable[A]): Translatable[List[A]] =
     Translatable((value, delta) => value.map(t.translate(_, delta)))