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-rw-r--r--docs/examples/monads/callccInterpreter.scala86
-rw-r--r--docs/examples/monads/directInterpreter.scala55
-rw-r--r--docs/examples/monads/errorInterpreter.scala86
-rw-r--r--docs/examples/monads/simpleInterpreter.scala75
-rw-r--r--docs/examples/monads/stateInterpreter.scala86
5 files changed, 0 insertions, 388 deletions
diff --git a/docs/examples/monads/callccInterpreter.scala b/docs/examples/monads/callccInterpreter.scala
deleted file mode 100644
index 5b556bd8fa..0000000000
--- a/docs/examples/monads/callccInterpreter.scala
+++ /dev/null
@@ -1,86 +0,0 @@
-object callccInterpreter {
-
- def id[a](x: a) = x
-
- type Answer = Value;
-
- case class M[A](in: (A => Answer) => Answer) {
- def bind[B](k: A => M[B]) = M[B](c => in (a => k(a) in c));
- def map[B](f: A => B): M[B] = bind(x => unitM(f(x)));
- def flatMap[B](f: A => M[B]): M[B] = bind(f);
- }
-
- def unitM[A](a: A) = M[A](c => c(a));
-
- def showM(m: M[Value]): String = (m in id).toString();
-
- def callCC[A](h: (A => M[A]) => M[A]) =
- M[A](c => h(a => M[A](d => c(a))) in c);
-
- type Name = String;
-
- trait Term;
- case class Var(x: Name) extends Term;
- case class Con(n: Int) extends Term;
- case class Add(l: Term, r: Term) extends Term;
- case class Lam(x: Name, body: Term) extends Term;
- case class App(fun: Term, arg: Term) extends Term;
- case class Ccc(x: Name, t: Term) extends Term;
-
- trait Value;
- case object Wrong extends Value {
- override def toString() = "wrong"
- }
- case class Num(n: Int) extends Value {
- override def toString() = n.toString();
- }
- case class Fun(f: Value => M[Value]) extends Value {
- override def toString() = "<function>"
- }
-
- type Environment = List[Pair[Name, Value]];
-
- def lookup(x: Name, e: Environment): M[Value] = e match {
- case List() => unitM(Wrong)
- case Pair(y, b) :: e1 => if (x == y) unitM(b) else lookup(x, e1)
- }
-
- def add(a: Value, b: Value): M[Value] = Pair(a, b) match {
- case Pair(Num(m), Num(n)) => unitM(Num(m + n))
- case _ => unitM(Wrong)
- }
-
- def apply(a: Value, b: Value): M[Value] = a match {
- case Fun(k) => k(b)
- case _ => unitM(Wrong)
- }
-
- def interp(t: Term, e: Environment): M[Value] = t match {
- case Var(x) => lookup(x, e)
- case Con(n) => unitM(Num(n))
- case Add(l, r) => for (a <- interp(l, e);
- b <- interp(r, e);
- c <- add(a, b))
- yield c
- case Lam(x, t) => unitM(Fun(a => interp(t, Pair(x, a) :: e)))
- case App(f, t) => for (a <- interp(f, e);
- b <- interp(t, e);
- c <- apply(a, b))
- yield c
- case Ccc(x, t) => callCC(k => interp(t, Pair(x, Fun(k)) :: e))
- }
-
- def test(t: Term): String =
- showM(interp(t, List()));
-
- val term0 = App(Lam("x", Add(Var("x"), Var("x"))), Add(Con(10), Con(11)));
- val term1 = App(Con(1), Con(2));
- val term2 = Add(Con(1), Ccc("k", Add(Con(2), App(Var("k"), Con(4)))));
-
- def main(args: Array[String]) = {
- System.out.println(test(term0));
- System.out.println(test(term1));
- System.out.println(test(term2));
- }
-}
-
diff --git a/docs/examples/monads/directInterpreter.scala b/docs/examples/monads/directInterpreter.scala
deleted file mode 100644
index 06fffba8e2..0000000000
--- a/docs/examples/monads/directInterpreter.scala
+++ /dev/null
@@ -1,55 +0,0 @@
-object directInterpreter {
-
- type Name = String;
-
- trait Term;
- case class Var(x: Name) extends Term;
- case class Con(n: Int) extends Term;
- case class Add(l: Term, r: Term) extends Term;
- case class Lam(x: Name, body: Term) extends Term;
- case class App(fun: Term, arg: Term) extends Term;
-
- trait Value;
- case object Wrong extends Value;
- case class Num(n: Int) extends Value;
- case class Fun(f: Value => Value)extends Value;
-
- def showval(v: Value): String = v match {
- case Wrong => "<wrong>"
- case Num(n) => n.toString()
- case Fun(f) => "<function>"
- }
-
- type Environment = List[Pair[Name, Value]];
-
- def lookup(x: Name, e: Environment): Value = e match {
- case List() => Wrong
- case Pair(y, b) :: e1 => if (x == y) b else lookup(x, e1)
- }
-
- def add(a: Value, b: Value): Value = Pair(a, b) match {
- case Pair(Num(m), Num(n)) => Num(m + n)
- case _ => Wrong
- }
-
- def apply(a: Value, b: Value) = a match {
- case Fun(k) => k(b)
- case _ => Wrong
- }
-
- def interp(t: Term, e: Environment): Value = t match {
- case Var(x) => lookup(x, e)
- case Con(n) => Num(n)
- case Add(l, r) => add(interp(l, e), interp(r, e))
- case Lam(x, t) => Fun(a => interp(t, Pair(x, a) :: e))
- case App(f, t) => apply(interp(f, e), interp(t, e))
- }
-
- def test(t: Term): String =
- showval(interp(t, List()));
-
- val term0 = App(Lam("x", Add(Var("x"), Var("x"))), Add(Con(10), Con(11)));
-
- def main(args: Array[String]) =
- System.out.println(test(term0));
-}
diff --git a/docs/examples/monads/errorInterpreter.scala b/docs/examples/monads/errorInterpreter.scala
deleted file mode 100644
index d3cc45627d..0000000000
--- a/docs/examples/monads/errorInterpreter.scala
+++ /dev/null
@@ -1,86 +0,0 @@
-object errorInterpreter {
-
- trait M[A] {
- def show: String
- def bind[B](k: A => M[B]): M[B]
- def map[B](f: A => B): M[B] = bind(x => unitM(f(x)))
- def flatMap[B](f: A => M[B]): M[B] = bind(f)
- }
-
- def unitM[A](a: A): M[A] = new Suc(a)
- def errorM[A](msg: String): M[A] = new Err(msg)
-
- def showM(m: M[Value]): String = m.show
-
- class Suc[A](x: A) extends M[A] {
- def bind[B](k: A => M[B]): M[B] = k(x)
- def show: String = "Success: " + x
- }
- class Err[A](msg: String) extends M[A] {
- def bind[B](k: A => M[B]): M[B] = new Err(msg)
- def show: String = "Error: " + msg
- }
-
- type Name = String
-
- trait Term
- case class Var(x: Name) extends Term
- case class Con(n: Int) extends Term
- case class Add(l: Term, r: Term) extends Term
- case class Lam(x: Name, body: Term) extends Term
- case class App(fun: Term, arg: Term) extends Term
-
- trait Value
- case object Wrong extends Value {
- override def toString() = "wrong"
- }
- case class Num(n: Int) extends Value {
- override def toString() = n.toString()
- }
- case class Fun(f: Value => M[Value]) extends Value {
- override def toString() = "<function>"
- }
-
- type Environment = List[Pair[Name, Value]]
-
- def lookup(x: Name, e: Environment): M[Value] = e match {
- case List() => errorM("unbound variable: " + x);
- case Pair(y, b) :: e1 => if (x == y) unitM(b) else lookup(x, e1)
- }
-
- def add(a: Value, b: Value): M[Value] = Pair(a, b) match {
- case Pair(Num(m), Num(n)) => unitM(Num(m + n))
- case _ => errorM("should be numbers: " + a + "," + b)
- }
-
- def apply(a: Value, b: Value): M[Value] = a match {
- case Fun(k) => k(b)
- case _ => errorM("should be function: " + a)
- }
-
- def interp(t: Term, e: Environment): M[Value] = t match {
- case Var(x) => lookup(x, e)
- case Con(n) => unitM(Num(n))
- case Add(l, r) => for (a <- interp(l, e);
- b <- interp(r, e);
- c <- add(a, b))
- yield c
- case Lam(x, t) => unitM(Fun(a => interp(t, Pair(x, a) :: e)))
- case App(f, t) => for (a <- interp(f, e);
- b <- interp(t, e);
- c <- apply(a, b))
- yield c
- }
-
- def test(t: Term): String =
- showM(interp(t, List()))
-
- val term0 = App(Lam("x", Add(Var("x"), Var("x"))), Add(Con(10), Con(11)))
- val term1 = App(Con(1), Con(2))
-
- def main(args: Array[String]) = {
- System.out.println(test(term0))
- System.out.println(test(term1))
- }
-}
-
diff --git a/docs/examples/monads/simpleInterpreter.scala b/docs/examples/monads/simpleInterpreter.scala
deleted file mode 100644
index cde3a92dbb..0000000000
--- a/docs/examples/monads/simpleInterpreter.scala
+++ /dev/null
@@ -1,75 +0,0 @@
-object simpleInterpreter {
-
- case class M[A](value: A) {
- def bind[B](k: A => M[B]): M[B] = k(value);
- def map[B](f: A => B): M[B] = bind(x => unitM(f(x)));
- def flatMap[B](f: A => M[B]): M[B] = bind(f);
- }
-
- def unitM[A](a: A): M[A] = M(a);
-
- def showM(m: M[Value]): String = m.value.toString();
-
- type Name = String;
-
- trait Term;
- case class Var(x: Name) extends Term;
- case class Con(n: Int) extends Term;
- case class Add(l: Term, r: Term) extends Term;
- case class Lam(x: Name, body: Term) extends Term;
- case class App(fun: Term, arg: Term) extends Term;
-
- trait Value;
- case object Wrong extends Value {
- override def toString() = "wrong"
- }
- case class Num(n: Int) extends Value {
- override def toString() = n.toString();
- }
- case class Fun(f: Value => M[Value]) extends Value {
- override def toString() = "<function>"
- }
-
- type Environment = List[Pair[Name, Value]];
-
- def lookup(x: Name, e: Environment): M[Value] = e match {
- case List() => unitM(Wrong)
- case Pair(y, b) :: e1 => if (x == y) unitM(b) else lookup(x, e1)
- }
-
- def add(a: Value, b: Value): M[Value] = Pair(a, b) match {
- case Pair(Num(m), Num(n)) => unitM(Num(m + n))
- case _ => unitM(Wrong)
- }
-
- def apply(a: Value, b: Value): M[Value] = a match {
- case Fun(k) => k(b)
- case _ => unitM(Wrong)
- }
-
- def interp(t: Term, e: Environment): M[Value] = t match {
- case Var(x) => lookup(x, e)
- case Con(n) => unitM(Num(n))
- case Add(l, r) => for (a <- interp(l, e);
- b <- interp(r, e);
- c <- add(a, b))
- yield c
- case Lam(x, t) => unitM(Fun(a => interp(t, Pair(x, a) :: e)))
- case App(f, t) => for (a <- interp(f, e);
- b <- interp(t, e);
- c <- apply(a, b))
- yield c
- }
-
- def test(t: Term): String =
- showM(interp(t, List()));
-
- val term0 = App(Lam("x", Add(Var("x"), Var("x"))), Add(Con(10), Con(11)));
- val term1 = App(Con(1), Con(2));
-
- def main(args: Array[String]) = {
- System.out.println(test(term0));
- System.out.println(test(term1));
- }
-}
-
diff --git a/docs/examples/monads/stateInterpreter.scala b/docs/examples/monads/stateInterpreter.scala
deleted file mode 100644
index 97f3335dab..0000000000
--- a/docs/examples/monads/stateInterpreter.scala
+++ /dev/null
@@ -1,86 +0,0 @@
-package examples.monads;
-
-object stateInterpreter {
-
- type State = Int;
-
- val tickS = new M(s => Pair((), s + 1));
-
- case class M[A](in: State => Pair[A, State]) {
- def bind[B](k: A => M[B]) = M[B]{ s0 =>
- val Pair(a, s1) = this in s0; k(a) in s1
- }
- def map[B](f: A => B): M[B] = bind(x => unitM(f(x)));
- def flatMap[B](f: A => M[B]): M[B] = bind(f);
- }
-
- def unitM[A](a: A) = M[A](s => Pair(a, s));
-
- def showM(m: M[Value]): String = {
- val Pair(a, s1) = m in 0;
- "Value: " + a + "; Count: " + s1
- }
-
- type Name = String;
-
- trait Term;
- case class Var(x: Name) extends Term;
- case class Con(n: Int) extends Term;
- case class Add(l: Term, r: Term) extends Term;
- case class Lam(x: Name, body: Term) extends Term;
- case class App(fun: Term, arg: Term) extends Term;
-
- trait Value;
- case object Wrong extends Value {
- override def toString() = "wrong"
- }
- case class Num(n: Int) extends Value {
- override def toString() = n.toString();
- }
- case class Fun(f: Value => M[Value]) extends Value {
- override def toString() = "<function>"
- }
-
- type Environment = List[Pair[Name, Value]];
-
- def lookup(x: Name, e: Environment): M[Value] = e match {
- case List() => unitM(Wrong)
- case Pair(y, b) :: e1 => if (x == y) unitM(b) else lookup(x, e1)
- }
-
- def add(a: Value, b: Value): M[Value] = Pair(a, b) match {
- case Pair(Num(m), Num(n)) => for (_ <- tickS) yield Num(m + n)
- case _ => unitM(Wrong)
- }
-
- def apply(a: Value, b: Value): M[Value] = a match {
- case Fun(k) => for (_ <- tickS; c <- k(b)) yield c
- case _ => unitM(Wrong)
- }
-
- def interp(t: Term, e: Environment): M[Value] = t match {
- case Var(x) => lookup(x, e)
- case Con(n) => unitM(Num(n))
- case Add(l, r) => for (a <- interp(l, e);
- b <- interp(r, e);
- c <- add(a, b))
- yield c
- case Lam(x, t) => unitM(Fun(a => interp(t, Pair(x, a) :: e)))
- case App(f, t) => for (a <- interp(f, e);
- b <- interp(t, e);
- c <- apply(a, b))
- yield c
- }
-
- def test(t: Term): String =
- showM(interp(t, List()));
-
- val term0 = App(Lam("x", Add(Var("x"), Var("x"))), Add(Con(10), Con(11)));
- val term1 = App(Con(1), Con(2));
-
- def main(args: Array[String]) = {
- System.out.println(test(term0));
- System.out.println(test(term1));
- }
-}
-
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-29 05:24:21 +0000