@forzaken hw1

build.sbt

@@ -1,3 +1,5 @@
+import scalariform.formatter.preferences._
+
 name := "fpspeedrun"
 
 version := "0.1"
@@ -9,4 +11,12 @@ scalacOptions += "-Ypartial-unification"
 libraryDependencies += "org.typelevel" %% "cats-core" % "1.1.0"
 libraryDependencies += "org.typelevel" %% "cats-effect" % "1.0.0-RC2"
 
-addCompilerPlugin("org.spire-math" %% "kind-projector" % "0.9.7")
+addCompilerPlugin("org.spire-math" %% "kind-projector" % "0.9.7")
+
+scalariformPreferences := scalariformPreferences.value
+  .setPreference(DanglingCloseParenthesis, Force)
+  .setPreference(AlignArguments, true)
+  .setPreference(AlignParameters, true)
+  .setPreference(AlignSingleLineCaseStatements, true)
+  .setPreference(DanglingCloseParenthesis, Force)
+  .setPreference(FirstParameterOnNewline, Force)

project/build.properties

@@ -0,0 +1 @@
+sbt.version=1.1.2

project/plugins.sbt

@@ -0,0 +1 @@
+addSbtPlugin("org.scalariform" % "sbt-scalariform" % "1.8.2")

src/main/scala/fpspeedrun/Eq.scala

@@ -1,5 +1,16 @@
 package fpspeedrun
 
+import fpspeedrun.syntax.eq._
+
 trait Eq[T] {
   def ===(x: T, y: T): Boolean
 }
+
+object Eq {
+  implicit def eqSeq[T: Eq]: Eq[Seq[T]] = (x: Seq[T], y: Seq[T]) => {
+    x.size == y.size && x.zip(y).forall {
+      case (a, b) =>
+        a === b
+    }
+  }
+}

src/main/scala/fpspeedrun/Ord.scala

@@ -1,15 +1,35 @@
 package fpspeedrun
 import fpspeedrun.Ord.Compare
+import fpspeedrun.syntax.ord._
 
-trait Ord[T] extends Eq[T]{
+trait Ord[T] extends Eq[T] {
   def compare(x: T, y: T): Compare
+
+  def ===(x: T, y: T): Boolean = {
+    compare(x, y) match {
+      case Compare.EQ => true
+      case _          => false
+    }
+  }
 }
 
-object Ord{
+object Ord {
   sealed trait Compare
-  object Compare{
-    case object LT //less than
-    case object EQ //equals to
-    case object GT //greater than
+  object Compare {
+    case object LT extends Compare //less than
+    case object EQ extends Compare //equals to
+    case object GT extends Compare //greater than
+  }
+
+  implicit def ordSeq[T: Ord]: Ord[Seq[T]] = (x: Seq[T], y: Seq[T]) => {
+    x.zip(y)
+      .collectFirst { case (a, b) if (a <> b) != Compare.EQ => a <> b }
+      .getOrElse {
+        (x.size, y.size) match {
+          case (a, b) if a > b  => Compare.GT
+          case (a, b) if a < b  => Compare.LT
+          case (a, b) if a == b => Compare.EQ
+        }
+      }
   }
 }

src/main/scala/fpspeedrun/Ratio.scala

@@ -1,4 +1,20 @@
 package fpspeedrun
 
-final case class Ratio()
+import fpspeedrun.Ord.Compare
 
+final case class Ratio(numerator: Int, denominator: Int)
+
+object Ratio {
+  implicit val eqRatio: Eq[Ratio] = (x: Ratio, y: Ratio) => {
+    x.numerator.toLong * y.denominator.toLong ==
+      x.denominator.toLong * y.numerator.toLong
+  }
+
+  implicit val ordRatio: Ord[Ratio] = (x: Ratio, y: Ratio) => {
+    (x.numerator.toLong * y.denominator.toLong, x.denominator.toLong * y.numerator.toLong) match {
+      case (a, b) if a > b  => Compare.GT
+      case (a, b) if a == b => Compare.EQ
+      case (a, b) if a < b  => Compare.LT
+    }
+  }
+}

src/main/scala/fpspeedrun/syntax.scala

@@ -1,9 +1,15 @@
 package fpspeedrun
 
 object syntax {
-  object eq{
-    implicit class EqOps[T](val x: T) extends AnyVal{
-      def ===(y: T)(implicit eq: Eq[T]): Boolean = eq.===(x, y)
+  object eq {
+    implicit class EqOps[T](val x: T) extends AnyVal {
+      def ===(y: T)(implicit ev: Eq[T]): Boolean = implicitly[Eq[T]].===(x, y)
+    }
+  }
+
+  object ord {
+    implicit class OrdOps[T](val x: T) extends AnyVal {
+      def <>(y: T)(implicit ev: Ord[T]): Ord.Compare = implicitly[Ord[T]].compare(x, y)
     }
   }
 }

src/main/scala/main/Day1.scala

@@ -0,0 +1,27 @@
+package main
+
+import fpspeedrun.Ord.Compare
+import fpspeedrun.Ratio
+import fpspeedrun.syntax.eq._
+import fpspeedrun.syntax.ord._
+import fpspeedrun.Ratio._
+
+object Day1 extends App {
+  assert(Ratio(1, 2) === Ratio(1, 2))
+  assert(!(Ratio(1, 2) === Ratio(1, 3)))
+  assert(Seq(Ratio(1, 2), Ratio(1, 3)) === Seq(Ratio(1, 2), Ratio(1, 3)))
+  assert(!(Seq(Ratio(1, 2), Ratio(1, 3)) === Seq(Ratio(1, 2), Ratio(1, 4))))
+}
+
+object Day1Homework extends App {
+  assert((Ratio(1, 2) <> Ratio(2, 3)) == Compare.LT)
+  assert((Ratio(5, 4) <> Ratio(2, 3)) == Compare.GT)
+  assert((Ratio(5, 4) <> Ratio(5, 4)) == Compare.EQ)
+
+  assert((Seq(Ratio(1, 2), Ratio(2, 3)) <> Seq(Ratio(1, 2), Ratio(2, 4))) == Compare.GT)
+  assert((Seq(Ratio(1, 2), Ratio(2, 4)) <> Seq(Ratio(1, 2), Ratio(2, 3))) == Compare.LT)
+
+  assert((Seq(Ratio(1, 2), Ratio(2, 3), Ratio(2, 3)) <> Seq(Ratio(1, 2), Ratio(2, 3))) == Compare.GT)
+  assert((Seq(Ratio(1, 2), Ratio(2, 3)) <> Seq(Ratio(1, 2), Ratio(2, 3), Ratio(2, 3))) == Compare.LT)
+  assert((Seq(Ratio(1, 2), Ratio(2, 3)) <> Seq(Ratio(1, 2), Ratio(2, 3))) == Compare.EQ)
+}