Add Reducer for LazyK

.scalafmt.conf

@@ -1,4 +1,4 @@
-maxColumn = 80
+maxColumn = 160
 version = 3.7.14
 runner.dialect = scala3
 preset = IntelliJ

catculator-core/src/main/scala/pl/writeonly/catculator/core/Extras.scala

@@ -4,9 +4,7 @@ import cats.data.NonEmptyList
 
 object Extras {
 
-  def foldNonEmpty[A](l: NonEmptyList[A])(f: (A, A) => A): A = l
-    .tail
-    .fold(l.head)(f)
+  def foldNonEmpty[A](l: NonEmptyList[A])(f: (A, A) => A): A = l.tail.fold(l.head)(f)
 
   def fix[T, R](f: (T => R) => (T => R)): (T => R) = new Function1[T, R] {
     def apply(t: T): R = f(this)(t)

catculator-core/src/main/scala/pl/writeonly/catculator/core/LambdaConfig.scala

@@ -6,24 +6,11 @@ import pl.writeonly.catculator.core.adt.calculus.Lambda
 import pl.writeonly.catculator.core.adt.calculus.Lambda._
 
 object LambdaConfig {
-  val haskellConfig: LambdaConfig = LambdaConfig(
-    apply = "apply",
-    pair = "pair",
-    nil = "nil",
-    succ = "succ",
-    zero = "zero",
-  )
-  val lambdaConfig: LambdaConfig =
-    LambdaConfig(apply = ";", pair = ",", nil = ".", succ = ":", zero = "0")
+  val haskellConfig: LambdaConfig = LambdaConfig(apply = "apply", pair = "pair", nil = "nil", succ = "succ", zero = "zero")
+  val lambdaConfig: LambdaConfig = LambdaConfig(apply = ";", pair = ",", nil = ".", succ = ":", zero = "0")
 }
 
-case class LambdaConfig(
-  apply: String,
-  pair: String,
-  nil: String,
-  succ: String,
-  zero: String,
-) {
+case class LambdaConfig(apply: String, pair: String, nil: String, succ: String, zero: String) {
 
   val thrushVariable: Var = Var(apply)
   val vireoVariable: Lambda = Var(pair)
@@ -40,17 +27,13 @@ case class LambdaConfig(
     l |> appAppAbs(applyBody, applyBody, apply)
   }
 
-  def appAppAbs(l1: Lambda, l2: Lambda, name: String)(l3: Lambda): Lambda =
-    App(l1, App(l2, Abs(name, l3)))
+  def appAppAbs(l1: Lambda, l2: Lambda, name: String)(l3: Lambda): Lambda = App(l1, App(l2, Abs(name, l3)))
 
-  def wrapAppThrush(l1: Lambda, name: String)(l2: Lambda): Lambda =
-    appAppAbs(thrushVariable, l1, name)(l2)
+  def wrapAppThrush(l1: Lambda, name: String)(l2: Lambda): Lambda = appAppAbs(thrushVariable, l1, name)(l2)
 
-  def reThrush(oldName: String, newName: String)(l: Lambda): Lambda =
-    wrapAppThrush(Var(oldName), newName)(l)
+  def reThrush(oldName: String, newName: String)(l: Lambda): Lambda = wrapAppThrush(Var(oldName), newName)(l)
 
-  def wrapAppVireoApp(l1: Lambda, l2: Lambda): Lambda =
-    App(App(vireoVariable, l1), l2)
+  def wrapAppVireoApp(l1: Lambda, l2: Lambda): Lambda = App(App(vireoVariable, l1), l2)
 
   def appSuccVariable(l: Lambda): Lambda = App(succVariable, l)
 }

catculator-core/src/main/scala/pl/writeonly/catculator/core/adt/calculus/Constants.scala

@@ -18,15 +18,9 @@ object Constants {
 
   def appK(a: CombinatorBT): Node[Combinator] = Node(kCom, a)
 
-  def app4(
-    c1: CombinatorBT,
-    c2: CombinatorBT,
-    c3: CombinatorBT,
-    c4: CombinatorBT,
-  ): CombinatorBT = Node(c1, app3(c2, c3, c4))
-
-  def app3(c1: CombinatorBT, c2: CombinatorBT, c3: CombinatorBT): CombinatorBT =
-    Node(c1, Node(c2, c3))
+  def app4(c1: CombinatorBT, c2: CombinatorBT, c3: CombinatorBT, c4: CombinatorBT): CombinatorBT = Node(c1, app3(c2, c3, c4))
+
+  def app3(c1: CombinatorBT, c2: CombinatorBT, c3: CombinatorBT): CombinatorBT = Node(c1, Node(c2, c3))
 
   def com(c: Combinator): CombinatorBT = Leaf(c)
 

catculator-core/src/main/scala/pl/writeonly/catculator/core/adt/calculus/InputEncoder.scala

@@ -15,13 +15,11 @@ object InputEncoder {
       },
   )
 
-  def encodeInput(input: List[Natural]): CombinatorBT = input
-    .foldRight(falseCom) { case (n, l) =>
-      cons(church(n), l)
-    }
+  def encodeInput(input: List[Natural]): CombinatorBT = input.foldRight(falseCom) { case (n, l) =>
+    cons(church(n), l)
+  }
 
-  def cons(a: CombinatorBT, b: CombinatorBT): CombinatorBT =
-    app3(sCom, Constants.app3SI(appK(a)), appK(b))
+  def cons(a: CombinatorBT, b: CombinatorBT): CombinatorBT = app3(sCom, Constants.app3SI(appK(a)), appK(b))
 
   def church(n: Natural): CombinatorBT = n.toBigInt match {
     case n if n === BigInt(0) => falseCom

catculator-core/src/main/scala/pl/writeonly/catculator/core/adt/calculus/Lambda.scala

@@ -28,25 +28,21 @@ object Lambda {
     .mkString
 
   // I know it is crazy, but I wanted to check it is possible
-  private val isOnlyCombinatorStep: (Lambda => Boolean) => Lambda => Boolean =
-    rec => {
-      case Com(_)    => true
-      case App(f, g) => rec(f) && rec(g)
-      case _         => false
-    }
+  private val isOnlyCombinatorStep: (Lambda => Boolean) => Lambda => Boolean = rec => {
+    case Com(_)    => true
+    case App(f, g) => rec(f) && rec(g)
+    case _         => false
+  }
 
   // I know it is crazy, but I wanted to check it is possible
   val isOnlyCombinator: Lambda => Boolean = fix(isOnlyCombinatorStep)
 
   def let1(t: (String, Lambda), body: Lambda): Lambda = Let(t._1, t._2, body)
 
-  def multi(params: List[String], body: NonEmptyList[Lambda]): Lambda =
-    MultiAbs(params, MultiApp(body))
+  def multi(params: List[String], body: NonEmptyList[Lambda]): Lambda = MultiAbs(params, MultiApp(body))
 
-  def multi1(head: Lambda, tail: List[Lambda]): Lambda =
-    MultiApp(NonEmptyList(head, tail))
-  def local1(head: Lambda, tail: List[Lambda]): Lambda =
-    LocalScope(NonEmptyList(head, tail))
+  def multi1(head: Lambda, tail: List[Lambda]): Lambda = MultiApp(NonEmptyList(head, tail))
+  def local1(head: Lambda, tail: List[Lambda]): Lambda = LocalScope(NonEmptyList(head, tail))
 
   def natNumFromString(s: String): Lambda = NatNum(Natural(s))
 

catculator-core/src/main/scala/pl/writeonly/catculator/core/adt/tree/Tree.scala

@@ -7,6 +7,5 @@ enum Tree[A]:
   case Node(children: NonEmptyList[Tree[A]])
 
 object Tree {
-  def node[A](head: Tree[A], tail: Tree[A]*): Tree[A] =
-    Node(NonEmptyList(head, tail.toList))
+  def node[A](head: Tree[A], tail: Tree[A]*): Tree[A] = Node(NonEmptyList(head, tail.toList))
 }

catculator-core/src/main/scala/pl/writeonly/catculator/core/calculators/lazyk/ADT.scala

@@ -2,11 +2,9 @@ package pl.writeonly.catculator.core.calculators.lazyk
 
 import pl.writeonly.catculator.core.adt.calculus.Combinator
 import pl.writeonly.catculator.core.adt.calculus.Combinator.CombinatorBT
+import pl.writeonly.catculator.core.adt.calculus.Constants
 import pl.writeonly.catculator.core.adt.tree.BinaryTree
 import pl.writeonly.catculator.core.adt.tree.BinaryTree._
-
-import pl.writeonly.catculator.core.adt.calculus.Constants
-
 import spire.math.Natural
 
 enum ADT:
@@ -17,16 +15,18 @@ enum ADT:
 object ADT {
 
   type ADTBT = BinaryTree[ADT]
+  type ADTBTSafe = Either[String, ADTBT]
 
-  val number0: ADTBT = Leaf(ADT.Num(Natural(0)))
+  val number0: ADTBT = Leaf(ADT.Num(Natural.zero))
+  val number1: ADTBT = Leaf(ADT.Num(Natural.one))
   val trueVar: ADTBT = fromCombinatorBT(Constants.trueCom)
   val falseVar: ADTBT = fromCombinatorBT(Constants.falseCom)
 
   def fromCombinatorBT(c: CombinatorBT): ADTBT = c match {
     case Node(a, b) => Node(fromCombinatorBT(a), fromCombinatorBT(b))
-    case Leaf(a) => Leaf(fromCombinator(a))
+    case Leaf(a)    => Leaf(fromCombinator(a))
   }
 
   private def fromCombinator(c: Combinator): ADT = ADT.Com(c)
 
-}
+}

catculator-core/src/main/scala/pl/writeonly/catculator/core/calculators/lazyk/Reducer.scala

@@ -0,0 +1,40 @@
+package pl.writeonly.catculator.core.calculators.lazyk
+
+import pl.writeonly.catculator.core.adt.calculus.Combinator
+import pl.writeonly.catculator.core.adt.calculus.Combinator._
+import pl.writeonly.catculator.core.adt.tree.BinaryTree
+import pl.writeonly.catculator.core.adt.tree.BinaryTree._
+import pl.writeonly.catculator.core.calculators.lazyk.ADT._
+import spire.math.Natural
+
+import scala.util.Right
+
+object Reducer {
+  def reduce(f: ADTBT): ADTBTSafe = f match {
+    case Node(x, y) => applyM(reduce(x), reduce(y))
+    case x          => Right(x)
+  }
+
+  def applyM(fM: ADTBTSafe, xM: ADTBTSafe): ADTBTSafe =
+    for
+      f <- fM
+      x <- xM
+      r <- apply(f, x)
+    yield r
+
+  def flippedApply(x: ADTBT, y: ADTBT): ADTBTSafe = apply(y, x)
+
+  def apply(f: ADTBT, x: ADTBT): ADTBTSafe = f match {
+    case Leaf(ADT.Succ())                   => succ(x)
+    case Node(Node(Leaf(ADT.Com(S)), z), y) => applyM(apply(z, x), apply(y, x))
+    case Node(Leaf(ADT.Com(K)), y)          => Right(y)
+    case Leaf(ADT.Com(I))                   => Right(x)
+    case _                                  => Right(Node(f, x))
+  }
+
+  private def succ(x: ADTBT) = x match {
+    case Leaf(ADT.Num(x)) => Right(Leaf(ADT.Num(x + Natural.one)))
+    case _                => Left(s"attempted to apply inc to a non-number $x")
+  }
+
+}

catculator-core/src/main/scala/pl/writeonly/catculator/core/parsers/HaskellParser.scala

@@ -19,8 +19,7 @@ object HaskellParser {
     c.isLetterOrDigit || c === '_'
   }
 
-  private val identifier: P[String] =
-    horizontalSymbol((identifierStart ~ identifierContinue.rep0).string)
+  private val identifier: P[String] = horizontalSymbol((identifierStart ~ identifierContinue.rep0).string)
 
   // format: off
   private val lambda: P[Lambda] = P.defer(
@@ -38,44 +37,33 @@ object HaskellParser {
 
   private val application0: P[Lambda] = lambda.rep.map(MultiApp.apply)
 
-  private val application: P[Lambda] = charSymbol('(') *> application0 <*
-    charHorizontalSymbol(')')
+  private val application: P[Lambda] = charSymbol('(') *> application0 <* charHorizontalSymbol(')')
 
-  private val let: P[Lambda] =
-    (
-      stringSymbol("let") *>
-        ((identifier <* stringSymbol("=")) ~ lambda) ~
-        (stringSymbol("in") *> lambda)
-    ).map(let1)
+  private val let: P[Lambda] = (stringSymbol("let") *> ((identifier <* stringSymbol("=")) ~ lambda) ~ (stringSymbol("in") *> lambda)).map(let1)
 
-  private val abstraction0 = charSymbol('\\') *> identifier.rep0 <*
-    stringSymbol("->")
+  private val abstraction0 = charSymbol('\\') *> identifier.rep0 <* stringSymbol("->")
 
-  private val abstraction: P[Lambda] = (abstraction0 ~ application0)
-    .map(MultiAbs.apply)
+  private val abstraction: P[Lambda] = (abstraction0 ~ application0).map(MultiAbs.apply)
 
   val charStr: P[Lambda] = horizontalSymbol(jsonString.map(CharStr.apply))
 
   private val apostrophe = P.char('\'')
 
-  val char: P[Lambda] = horizontalSymbol(apostrophe *> P.anyChar <* apostrophe)
-    .map { c =>
-      natNumFromLong(c.toLong)
-    }
+  val char: P[Lambda] = horizontalSymbol(apostrophe *> P.anyChar <* apostrophe).map { c =>
+    natNumFromLong(c.toLong)
+  }
 
   val natNum: P[Lambda] = horizontalSymbol(digits.map(natNumFromString))
 
-  private val function: P[Func] =
-    ((identifier <* charSymbol('=')) ~ symbol(lambda)).map(Func.apply)
+  private val function: P[Func] = ((identifier <* charSymbol('=')) ~ symbol(lambda)).map(Func.apply)
 
   private val functionParser: P[Func] = function <* P.end
 
   private val functionsParser = whitespaces *> function.rep <* P.end
 
   val parseFunction: String => Either[P.Error, Func] = functionParser.parseAll
 
-  val parseFunctions: String => Either[P.Error, NonEmptyList[Func]] =
-    functionsParser.parseAll
+  val parseFunctions: String => Either[P.Error, NonEmptyList[Func]] = functionsParser.parseAll
 
   val parse3: String => Either[P.Error, NonEmptyList[Func]] = (s) =>
     parseFunctions(s) match {

catculator-core/src/main/scala/pl/writeonly/catculator/core/parsers/LambdaParser.scala

@@ -19,8 +19,7 @@ object LambdaParser {
     c.isLetterOrDigit || c === '_'
   }
 
-  val identifier: P[String] =
-    symbol((identifierStart ~ identifierContinue.rep0).string)
+  val identifier: P[String] = symbol((identifierStart ~ identifierContinue.rep0).string)
 
   // format: off
   val lambda: P[Lambda] = P.defer(
@@ -38,26 +37,19 @@ object LambdaParser {
 
   val variable: P[Lambda] = identifier.map(Var.apply)
 
-  val abstraction: P[Lambda] = (charSymbol('\\') *> identifier ~ lambda)
-    .map(Abs.apply)
+  val abstraction: P[Lambda] = (charSymbol('\\') *> identifier ~ lambda).map(Abs.apply)
 
-  val application: P[Lambda] = (charSymbol('`') *> lambda ~ lambda)
-    .map(App.apply)
+  val application: P[Lambda] = (charSymbol('`') *> lambda ~ lambda).map(App.apply)
 
-  val mautiApplicationChildren: P[Lambda] = (lambda ~ lambda.rep0)
-    .map((multi1 _).tupled)
+  val mautiApplicationChildren: P[Lambda] = (lambda ~ lambda.rep0).map((multi1 _).tupled)
 
-  val multiApplication: P[Lambda] =
-    charSymbol('(') *> mautiApplicationChildren <* charSymbol(')')
+  val multiApplication: P[Lambda] = charSymbol('(') *> mautiApplicationChildren <* charSymbol(')')
 
-  val localScopeChildren: P[Lambda] = (lambda ~ lambda.rep0)
-    .map((local1 _).tupled)
+  val localScopeChildren: P[Lambda] = (lambda ~ lambda.rep0).map((local1 _).tupled)
 
-  val localScope: P[Lambda] = charSymbol('{') *> localScopeChildren <*
-    charSymbol('}')
+  val localScope: P[Lambda] = charSymbol('{') *> localScopeChildren <* charSymbol('}')
 
-  val nilList: P[Lambda] = charSymbol('[') *> lambda.rep0.map(NilList.apply) <*
-    charSymbol(']')
+  val nilList: P[Lambda] = charSymbol('[') *> lambda.rep0.map(NilList.apply) <* charSymbol(']')
 
   val charStr: P[Lambda] = jsonString.map(CharStr.apply)
 

catculator-core/src/main/scala/pl/writeonly/catculator/core/reducers/AbstractionReducer.scala

@@ -18,22 +18,17 @@ object AbstractionReducer {
     case l if isOnlyCombinator(l) => wrapAppK(l)
     case Var(n1)                  => reduceVar(p0, n1)
     case Abs(p1, b1)              => reduceAbs(p0, p1, b1)
-    case App(f, g) =>
-      wrapAppAppS(reduceAbstraction1(p0, f), reduceAbstraction1(p0, g))
-    case lambda => lambda
+    case App(f, g)                => wrapAppAppS(reduceAbstraction1(p0, f), reduceAbstraction1(p0, g))
+    case lambda                   => lambda
   }
 
-  private def reduceVar(n0: String, n1: String): Lambda =
-    ifElse(n0 === n1)(Com(I))(wrapAppK(Var(n1)))
+  private def reduceVar(n0: String, n1: String): Lambda = ifElse(n0 === n1)(Com(I))(wrapAppK(Var(n1)))
 
-  private def reduceAbs(p0: String, p1: String, b1: Lambda): Lambda =
-    reduceAbs1(p0, p1, reduceAbstraction1(p1, b1))
+  private def reduceAbs(p0: String, p1: String, b1: Lambda): Lambda = reduceAbs1(p0, p1, reduceAbstraction1(p1, b1))
 
-  private def reduceAbs1(p0: String, p1: String, c: Lambda): Lambda =
-    ifElse(p0 === p1)(wrapAppK(c))(reduceAbstraction1(p0, c))
+  private def reduceAbs1(p0: String, p1: String, c: Lambda): Lambda = ifElse(p0 === p1)(wrapAppK(c))(reduceAbstraction1(p0, c))
 
   private def wrapAppK(c: Lambda): Lambda = App(Com(K), c)
 
-  private def wrapAppAppS(c1: Lambda, c2: Lambda): Lambda =
-    App(App(Com(S), c1), c2)
+  private def wrapAppAppS(c1: Lambda, c2: Lambda): Lambda = App(App(Com(S), c1), c2)
 }