Optimize cats-core boilerplate

typelevel · May 8, 2021 · e4bea48 · e4bea48
1 parent 1671eb7
commit e4bea48
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diff --git a/project/Boilerplate.scala b/project/Boilerplate.scala
@@ -74,10 +74,6 @@ object Boilerplate {
       if (arity <= 2) "(*, *)"
       else `A..(N - 2)`.mkString("(", ", ", ", *, *)")
     val `a..(n - 1)` = (0 until (arity - 1)).map(n => s"a$n")
-    val `fa._1..fa._(n - 2)` =
-      if (arity <= 2) "" else (0 until (arity - 2)).map(n => s"fa._${n + 1}").mkString("", ", ", ", ")
-    val `pure(fa._1..(n - 2))` =
-      if (arity <= 2) "" else (0 until (arity - 2)).map(n => s"G.pure(fa._${n + 1})").mkString("", ", ", ", ")
     val `a0, a(n - 1)` = if (arity <= 1) "" else `a..(n - 1)`.mkString(", ")
     val `[A0, A(N - 1)]` = if (arity <= 1) "" else `A..(N - 1)`.mkString("[", ", ", "]")
     val `(A0, A(N - 1))` =
@@ -87,19 +83,15 @@ object Boilerplate {
     val `(A..N - 1, *)` =
       if (arity == 1) "Tuple1"
       else `A..(N - 1)`.mkString("(", ", ", ", *)")
-    val `(fa._1..(n - 1))` =
-      if (arity <= 1) "Tuple1.apply" else (0 until (arity - 1)).map(n => s"fa._${n + 1}").mkString("(", ", ", ", _)")
 
     def `A0, A(N - 1)&`(a: String): String =
       if (arity <= 1) s"Tuple1[$a]" else `A..(N - 1)`.mkString("(", ", ", s", $a)")
-
-    def `fa._1..(n - 1) & `(a: String): String =
-      if (arity <= 1) s"Tuple1($a)" else (0 until (arity - 1)).map(n => s"fa._${n + 1}").mkString("(", ", ", s", $a)")
-
-    def `constraints A..N`(c: String): String = synTypes.map(tpe => s"$tpe: $c[$tpe]").mkString("(implicit ", ", ", ")")
+    def `constraints A..N`(c: String): String =
+      synTypes.map(tpe => s"$tpe: $c[$tpe]").mkString("(implicit ", ", ", ")")
     def `constraints A..(N-1)`(c: String): String =
       if (arity <= 1) "" else `A..(N - 1)`.map(tpe => s"$tpe: $c[$tpe]").mkString("(implicit ", ", ", ")")
-    def `parameters A..(N-1)`(c: String): String = `A..(N - 1)`.map(tpe => s"$tpe: $c[$tpe]").mkString(", ")
+    def `parameters A..(N-1)`(c: String): String =
+      `A..(N - 1)`.map(tpe => s"$tpe: $c[$tpe]").mkString(", ")
   }
 
   trait Template {

diff --git a/project/TupleBifunctorInstancesBoiler.scala b/project/TupleBifunctorInstancesBoiler.scala
@@ -5,7 +5,7 @@ import Boilerplate.{Template, TemplateVals}
 import sbt.File
 
 object GenTupleBifunctorInstances extends Template {
-  override def range = 1 to 11
+  override def range = 2 to 11
   override def filename(root: sbt.File): File =
     root / "cats" / "instances" / "NTupleBifunctorInstances.scala"
 
@@ -18,15 +18,17 @@ object GenTupleBifunctorInstances extends Template {
     |package instances
     |
     |private[cats] trait NTupleBifunctorInstances {
-${if (arity > 1)
-      block"""
+    |
+    |  private def instance[F[_, _]](bim: (F[Any, Any], Any => Any, Any => Any) => F[Any, Any]): Bifunctor[F] =
+    |    new Bifunctor[F] {
+    |      def bimap[A, B, C, D](fab: F[A, B])(f: A => C, g: B => D): F[C, D] =
+    |        bim(fab.asInstanceOf[F[Any, Any]], f.asInstanceOf[Any => Any], g.asInstanceOf[Any => Any]).asInstanceOf[F[C, D]]
+    |    }
+    -
     -  implicit final def catsStdBifunctorForTuple$arity${`[A0, A(N - 2)]`}: Bifunctor[${`(A..N - 2, *, *)`}] =
-    -    new Bifunctor[${`(A..N - 2, *, *)`}] {
-    -      def bimap[A, B, C, D](fa: (${`A0, A(N - 2)`}A, B))(f: A => C, g: B => D): (${`A0, A(N - 2)`}C, D) = (${`fa._1..fa._(n - 2)`}f(fa._${arity - 1}), g(fa._$arity))
-    -    }"""
-    else
-      block"""
-    -"""}
+    -    instance[${`(A..N - 2, *, *)`}] { (fab, f, g) =>
+    -      fab.copy(_${arity - 1} = f(fab._${arity - 1}), _$arity = g(fab._$arity))
+    -    }
     |}"""
   }
 }
diff --git a/project/TupleBitraverseInstancesBoiler.scala b/project/TupleBitraverseInstancesBoiler.scala
@@ -5,7 +5,7 @@ import Boilerplate.{Template, TemplateVals}
 import sbt.File
 
 object GenTupleBitraverseInstances extends Template {
-  override def range = 1 to 11
+  override def range = 2 to 11
   override def filename(root: sbt.File): File =
     root / "cats" / "instances" / "NTupleBitraverseInstances.scala"
 
@@ -18,20 +18,35 @@ object GenTupleBitraverseInstances extends Template {
     |package instances
     |
     |private[cats] trait NTupleBitraverseInstances {
-${if (arity > 1)
-      block"""
+    |  protected type γ[_]
+    |  
+    |  private def instance[F[_, _] <: Product](
+    |    bitrav: (F[Any, Any], Applicative[γ], Any => γ[Any], Any => γ[Any]) => γ[F[Any, Any]]
+    |  ): Bitraverse[F] = new Bitraverse[F] {
+    |    def bitraverse[G[_], A, B, C, D](fab: F[A, B])(f: A => G[C], g: B => G[D])(implicit G: Applicative[G]): G[F[C, D]] =
+    |      bitrav(
+    |        fab.asInstanceOf[F[Any, Any]],
+    |        G.asInstanceOf[Applicative[γ]],
+    |        f.asInstanceOf[Any => γ[Any]],
+    |        g.asInstanceOf[Any => γ[Any]]
+    |      ).asInstanceOf[G[F[C, D]]]
+    |      
+    |    @inline private def last1[A, B](fab: F[A, B]): A =
+    |      fab.productElement(fab.productArity - 2).asInstanceOf[A]
+    |    @inline private def last2[A, B](fab: F[A, B]): B =
+    |      fab.productElement(fab.productArity - 1).asInstanceOf[B]
+    |    def bifoldLeft[A, B, C](fab: F[A, B], c: C)(f: (C, A) => C, g: (C, B) => C): C =
+    |      g(f(c, last1(fab)), last2(fab))
+    |    def bifoldRight[A, B, C](fab: F[A, B], c: Eval[C])(f: (A, Eval[C]) => Eval[C], g: (B, Eval[C]) => Eval[C]): Eval[C] =
+    |      g(last2(fab), f(last1(fab), c))
+    |  }
+    -
     -  implicit final def catsStdBitraverseForTuple$arity${`[A0, A(N - 2)]`}: Bitraverse[${`(A..N - 2, *, *)`}] =
-    -    new Bitraverse[${`(A..N - 2, *, *)`}] {
-    -      def bitraverse[G[_], A, B, C, D](fa: (${`A0, A(N - 2)`}A, B))(f: A => G[C], g: B => G[D])(implicit G: Applicative[G]): G[(${`A0, A(N - 2)`}C, D)] =
-    -        G.tuple$arity(${`pure(fa._1..(n - 2))`}f(fa._${arity - 1}), g(fa._$arity))
-    -      def bifoldLeft[A, B, C](fa: (${`A0, A(N - 2)`}A, B), c: C)(f: (C, A) => C, g: (C, B) => C): C =
-    -        g(f(c, fa._${arity - 1}), fa._$arity)
-    -      def bifoldRight[A, B, C](fa: (${`A0, A(N - 2)`}A, B), c: Eval[C])(f: (A, Eval[C]) => Eval[C], g: (B, Eval[C]) => Eval[C]): Eval[C] =
-    -        g(fa._$arity, f(fa._${arity - 1}, c))
-    -    }"""
-    else
-      block"""
-    -"""}
+    -    instance { (fab, G, f, g) =>
+    -      G.map2(f(fab._${arity - 1}), g(fab._$arity)) { (x, y) =>
+    -        fab.copy(_${arity - 1} = x, _$arity = y)
+    -      }
+    -    }
     |}"""
   }
 }
diff --git a/project/TupleMonadInstancesBoiler.scala b/project/TupleMonadInstancesBoiler.scala
@@ -56,49 +56,47 @@ object GenTupleMonadInstances extends Template {
     |import scala.annotation.tailrec
     |
     |private[cats] trait NTupleMonadInstances extends NTupleMonadInstances1 {
+    |
+    |  private def instance[F[_] <: Product](cofMap: (F[Any], F[Any] => Any) => F[Any]): Comonad[F] =
+    |    new Comonad[F] {
+    |      def coflatMap[A, B](fa: F[A])(f: F[A] => B) =
+    |        cofMap(fa.asInstanceOf[F[Any]], f.asInstanceOf[F[Any] => Any]).asInstanceOf[F[B]]
+    |      def extract[A](fa: F[A]) =
+    |        fa.productElement(fa.productArity - 1).asInstanceOf[A]
+    |      def map[A, B](fa: F[A])(f: A => B) =
+    |        coflatMap(fa)(fa => f(extract(fa)))
+    |    }
+    -
     -  implicit final def catsStdInstancesForTuple$arity${`[A0, A(N - 1)]`}: Comonad[${`(A..N - 1, *)`}] =
-    -    new Comonad[${`(A..N - 1, *)`}] {
-    -      def coflatMap[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: (${`A0, A(N - 1)&`("A")}) => B): ${`A0, A(N - 1)&`(
-      "B"
-    )} = ${`fa._1..(n - 1) & `(
-      "f(fa)"
-    )}
-    -      def extract[A](fa: ${`A0, A(N - 1)&`("A")}): A = fa._$arity
-    -      override def map[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => B): ${`A0, A(N - 1)&`("B")} =
-    -        ${`fa._1..(n - 1) & `(s"f(fa._$arity)")}
-    -      override def coflatten[A](fa: ${`A0, A(N - 1)&`("A")}): $coflattenReturn = ${`fa._1..(n - 1) & `("fa")}
-    -    }
+    -    instance((fa, f) => fa.copy(_$arity = f(fa)))
     |}
-    |private[cats] sealed trait NTupleMonadInstances1 extends NTupleMonadInstances2 {
+    |private[cats] sealed trait NTupleMonadInstances1 extends NTupleMonadInstances2 { this: NTupleMonadInstances =>
     -  implicit final def catsStdCommutativeMonadForTuple$arity${`[A0, A(N - 1)]`}${`constraints A..(N-1)`(
       "CommutativeMonoid"
     )}: CommutativeMonad[${`(A..N - 1, *)`}] =
     -    new FlatMapTuple$arity${`[A0, A(N - 1)]`}(${`A0, A(N - 1)`}) with CommutativeMonad[${`(A..N - 1, *)`}] {
     -      def pure[A](a: A): ${`A0, A(N - 1)&`("A")} = $monadPureMethod
     -    }
     |}
-    |private[cats] sealed trait NTupleMonadInstances2 extends NTupleMonadInstances3 {
+    |private[cats] sealed trait NTupleMonadInstances2 extends NTupleMonadInstances3 { this: NTupleMonadInstances =>
     -  implicit final def catsStdCommutativeFlatMapForTuple$arity${`[A0, A(N - 1)]`}${`constraints A..(N-1)`(
       "CommutativeSemigroup"
     )}: CommutativeFlatMap[${`(A..N - 1, *)`}] =
     -    new FlatMapTuple$arity${`[A0, A(N - 1)]`}(${`A0, A(N - 1)`}) with CommutativeFlatMap[${`(A..N - 1, *)`}]
     |}
-    |private[cats] sealed trait NTupleMonadInstances3 extends NTupleMonadInstances4 {
+    |private[cats] sealed trait NTupleMonadInstances3 extends NTupleMonadInstances4 { this: NTupleMonadInstances =>
     -  implicit def catsStdMonadForTuple$arity${`[A0, A(N - 1)]`}${`constraints A..(N-1)`("Monoid")}: Monad[${`(A..N - 1, *)`}] =
     -    new FlatMapTuple$arity${`[A0, A(N - 1)]`}(${`A0, A(N - 1)`}) with Monad[${`(A..N - 1, *)`}] {
     -      def pure[A](a: A): ${`A0, A(N - 1)&`("A")} = $monadPureMethod
     -    }
     |}
-    |private[cats] sealed trait NTupleMonadInstances4 extends NTupleMonadInstances5 {
+    |private[cats] sealed trait NTupleMonadInstances4 extends NTupleMonadInstances5 { this: NTupleMonadInstances =>
     -  implicit def catsStdFlatMapForTuple$arity${`[A0, A(N - 1)]`}${`constraints A..(N-1)`("Semigroup")}: FlatMap[${`(A..N - 1, *)`}] =
     -    new FlatMapTuple$arity${`[A0, A(N - 1)]`}(${`A0, A(N - 1)`})
     |}
-    |private[cats] sealed trait NTupleMonadInstances5 {
+    |private[cats] sealed trait NTupleMonadInstances5 { this: NTupleMonadInstances =>
     -  implicit def catsStdInvariantForTuple$arity${`[A0, A(N - 1)]`}: Invariant[${`(A..N - 1, *)`}] =
-    -    new Invariant[${`(A..N - 1, *)`}] {
-    -      def imap[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => B)(g: B => A): ${`A0, A(N - 1)&`("B")} =
-    -        ${`fa._1..(n - 1) & `(s"f(fa._$arity)")}
-    -    }
+    -    catsStdInstancesForTuple$arity
     |}
     -
     -private[instances] class $flatMapTupleClass${`[A0, A(N - 1)]`}(${`parameters A..(N-1)`("Semigroup")}) extends FlatMap[${`(A..N - 1, *)`}] {
@@ -107,7 +105,7 @@ object GenTupleMonadInstances extends Template {
     -  override def product[A, B](fa: ${`A0, A(N - 1)&`("A")}, fb: ${`A0, A(N - 1)&`("B")}): ${`A0, A(N - 1)&`("(A, B)")} =
     -    ${`combine A..(N - 1)`("fa", "fb", s"(fa._$arity, fb._$arity)")}
     -  override def map[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => B): ${`A0, A(N - 1)&`("B")} =
-    -    ${`fa._1..(n - 1) & `(s"f(fa._$arity)")}
+    -    fa.copy(_$arity = f(fa._$arity))
     -  def flatMap[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => ${`A0, A(N - 1)&`("B")}): ${`A0, A(N - 1)&`("B")} = {
          ${if (arity > 1) block"""
          -    val xb = f(fa._$arity)

diff --git a/project/TupleShowInstancesBoiler.scala b/project/TupleShowInstancesBoiler.scala
@@ -26,9 +26,7 @@ object GenTupleShowInstances extends Template {
     |
     |private[cats] trait NTupleShowInstances {
     -  implicit final def catsStdShowForTuple$arity[${`A..N`}]${`constraints A..N`("Show")}: Show[${`(A..N)`}] =
-    -    new Show[${`(A..N)`}] {
-    -      def show(f: ${`(A..N)`}): String = $showMethod
-    -    }
+    -    f => $showMethod
     |}"""
   }
 }
diff --git a/project/TupleUnorderedFoldableInstancesBoiler.scala b/project/TupleUnorderedFoldableInstancesBoiler.scala
@@ -18,33 +18,37 @@ object GenTupleUnorderedFoldableInstances extends Template {
     |package instances
     |
     |private[cats] trait NTupleUnorderedFoldableInstances {
--  implicit final def catsUnorderedFoldableInstancesForTuple$arity${`[A0, A(N - 1)]`}: Traverse[${`(A..N - 1, *)`}] with Reducible[${`(A..N - 1, *)`}] =
--    new Traverse[${`(A..N - 1, *)`}] with Reducible[${`(A..N - 1, *)`}] {
--      def traverse[G[_], A, B](fa: ${`A0, A(N - 1)&`(
-      "A"
-    )})(f: A => G[B])(implicit G: Applicative[G]): G[${`A0, A(N - 1)&`(
-      "B"
-    )}] =
--        G.map(f(fa._$arity))(${`(fa._1..(n - 1))`})
--      def foldLeft[A, B](fa: ${`A0, A(N - 1)&`("A")}, b: B)(f: (B, A) => B): B = f(b, fa._$arity)
--      def foldRight[A, B](fa: ${`A0, A(N - 1)&`("A")}, lb: Eval[B])(f: (A, Eval[B]) => Eval[B]): Eval[B] = f(fa._$arity, lb)
--      override def map[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => B): ${`A0, A(N - 1)&`("B")} =
--        ${`fa._1..(n - 1) & `(s"f(fa._$arity)")}
--      override def foldMap[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => B)(implicit B: Monoid[B]): B = f(fa._$arity)
--      override def reduce[A](fa: ${`A0, A(N - 1)&`("A")})(implicit A: Semigroup[A]): A = fa._$arity
--      def reduceLeftTo[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => B)(g: (B, A) => B): B = f(fa._$arity)
--      override def reduceLeft[A](fa: ${`A0, A(N - 1)&`("A")})(f: (A, A) => A): A = fa._$arity
--      override def reduceLeftToOption[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => B)(g: (B, A) => B): Option[B] = Some(f(fa._$arity))
--      override def reduceRight[A](fa: ${`A0, A(N - 1)&`("A")})(f: (A, Eval[A]) => Eval[A]): Eval[A] = Now(fa._$arity)
--      def reduceRightTo[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => B)(g: (A, Eval[B]) => Eval[B]): Eval[B] = Now(f(fa._$arity))
--      override def reduceRightToOption[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => B)(g: (A, Eval[B]) => Eval[B]): Eval[Option[B]] = Now(Some(f(fa._$arity)))
--      override def reduceMap[A, B](fa: ${`A0, A(N - 1)&`("A")})(f: A => B)(implicit B: Semigroup[B]): B = f(fa._$arity)
--      override def size[A](fa: ${`A0, A(N - 1)&`("A")}): Long = 1L
--      override def get[A](fa: ${`A0, A(N - 1)&`("A")})(idx: Long): Option[A] = if (idx == 0L) Some(fa._$arity) else None
--      override def exists[A](fa: ${`A0, A(N - 1)&`("A")})(p: A => Boolean): Boolean = p(fa._$arity)
--      override def forall[A](fa: ${`A0, A(N - 1)&`("A")})(p: A => Boolean): Boolean = p(fa._$arity)
--      override def isEmpty[A](fa: ${`A0, A(N - 1)&`("A")}): Boolean = false
--    }
+    |  protected type γ[_]
+    |
+    |  private def instance[F[_] <: Product](
+    |    trav: (F[Any], Applicative[γ], Any => γ[Any]) => γ[F[Any]]
+    |  ): Traverse[F] with Reducible[F] =
+    |    new Traverse[F] with Reducible[F] {
+    |      def traverse[G[_], A, B](fa: F[A])(f: A => G[B])(implicit G: Applicative[G]) =
+    |        trav(fa.asInstanceOf[F[Any]], G.asInstanceOf[Applicative[γ]], f.asInstanceOf[Any => γ[Any]]).asInstanceOf[G[F[B]]]
+    |      @inline private def last[A](fa: F[A]): A =
+    |        fa.productElement(fa.productArity - 1).asInstanceOf[A]
+    |      def foldLeft[A, B](fa: F[A], b: B)(f: (B, A) => B): B = f(b, last(fa))
+    |      def foldRight[A, B](fa: F[A], lb: Eval[B])(f: (A, Eval[B]) => Eval[B]): Eval[B] = f(last(fa), lb)
+    |      override def foldMap[A, B](fa: F[A])(f: A => B)(implicit B: Monoid[B]): B = f(last(fa))
+    |      override def reduce[A](fa: F[A])(implicit A: Semigroup[A]): A = last(fa)
+    |      def reduceLeftTo[A, B](fa: F[A])(f: A => B)(g: (B, A) => B): B = f(last(fa))
+    |      override def reduceLeft[A](fa: F[A])(f: (A, A) => A): A = last(fa)
+    |      override def reduceLeftToOption[A, B](fa: F[A])(f: A => B)(g: (B, A) => B): Option[B] = Some(f(last(fa)))
+    |      override def reduceRight[A](fa: F[A])(f: (A, Eval[A]) => Eval[A]): Eval[A] = Now(last(fa))
+    |      def reduceRightTo[A, B](fa: F[A])(f: A => B)(g: (A, Eval[B]) => Eval[B]): Eval[B] = Now(f(last(fa)))
+    |      override def reduceRightToOption[A, B](fa: F[A])(f: A => B)(g: (A, Eval[B]) => Eval[B]): Eval[Option[B]] = Now(Some(f(last(fa))))
+    |      override def reduceMap[A, B](fa: F[A])(f: A => B)(implicit B: Semigroup[B]): B = f(last(fa))
+    |      override def size[A](fa: F[A]): Long = 1L
+    |      override def get[A](fa: F[A])(idx: Long): Option[A] = if (idx == 0L) Some(last(fa)) else None
+    |      override def exists[A](fa: F[A])(p: A => Boolean): Boolean = p(last(fa))
+    |      override def forall[A](fa: F[A])(p: A => Boolean): Boolean = p(last(fa))
+    |      override def isEmpty[A](fa: F[A]): Boolean = false
+    |    }
+    -
+    -  implicit final def catsUnorderedFoldableInstancesForTuple$arity${`[A0, A(N - 1)]`}
+    -    : Traverse[${`(A..N - 1, *)`}] with Reducible[${`(A..N - 1, *)`}]
+    -    = instance((fa, G, f) => G.map(f(fa._$arity))(x => fa.copy(_$arity = x)))
     |}"""
   }
 }