Merge branch 'feature/fasteffekt-list' into feature/fasteffekt

examples/fasteffekt/harness.effekt

@@ -2,6 +2,7 @@ module examples/fasteffekt/harness
 
 
 import examples/fasteffekt/permute
+import examples/fasteffekt/list
 import io/args
 import text/string
 
@@ -56,16 +57,17 @@ def doRuns(innerIterations: Int, iterations: Int){benchmark: Int=>Unit} = {
 def doBenchmark(name: String, inner: Int, iterations: Int) = {
     if (name == "Permute") {
         doRuns(inner, iterations){Permute}
+    } else if (name == "List") {
+        doRuns(inner, iterations){List}
     } else {
         panic("unknown benchmark")
     }
 }
 
-def main() = {
+def attemptBenchmarkExec(args: List[String]) = {
     val debugStartTime : Int = currentTimeNanos();
 
-
-    ["Permute","100", "100"] match {
+    args match {
         case Cons(x, Cons(y, Cons(z, Nil()))) => 
             (x, toInt(y), toInt(z)) match {
                 case (benchName, Some(iterations), Some(innerIterations)) => 
@@ -80,3 +82,7 @@ def main() = {
     println("DEBUG: runner total took: " ++ show(runTime) ++ " us");
 }
 
+def main() = {
+    attemptBenchmarkExec(["List","100", "100"])
+}
+

examples/fasteffekt/list.effekt

@@ -0,0 +1,81 @@
+import examples/fasteffekt/benchmark
+
+record Element (
+    value: Int, child: Option[Element]
+)
+
+def length(element: Option[Element]): Int = 
+    element match {
+        case None() => return 0;
+        case Some(Element(value, child)) => return 1 + length(child) 
+    }
+
+def isShorterThan(x: Option[Element], y: Option[Element]): Boolean = {
+    var xTail:Option[Element] = x;
+    var yTail:Option[Element] = y;
+    var run = true;
+    var bigger = false;
+    while (run) {
+        (xTail,yTail) match {
+            case (_, None()) => run = false; bigger = false;
+            case (None(), _) => run =false; bigger = true;
+            case (Some(xx),Some(yy)) => xTail = xx.child; yTail = yy.child;
+        }
+    }
+    return bigger;
+}
+
+def makeList(lenght: Int): Option[Element] = {
+    return if(lenght == 0) {
+        None()
+    } else {
+        Some(Element(0, makeList(lenght-1)))
+    }
+}
+
+//no idea what that function does.
+def tail(x: Option[Element], y: Option[Element], z: Option[Element]): Option[Element] = {
+    if (y.isShorterThan(x)) {
+        (x,y,z) match {
+            case (Some(xx),Some(yy),Some(zz)) => 
+                val yChild : Option[Element] = yy.child;
+                val zChild : Option[Element] = zz.child;
+                val xChild : Option[Element] = xx.child;
+
+                val xxx: Option[Element] = tail(xChild, y, z);
+                val yyy: Option[Element] = tail(yChild, z, x);
+                val zzz: Option[Element] = tail(zChild, x, y);
+                tail(
+                    xxx,
+                    yyy,
+                    zzz
+                )
+            case _ => panic("oh no!");
+        }
+    } else {
+        z;
+    }
+}
+
+def List(_: Int) = {
+    def benchmark(): Int = {
+        val result = 
+        tail(
+            makeList(15),
+            makeList(10),
+            makeList(6)
+        );
+        length(result);
+    }
+
+
+    def verifyResult(result: Int): Boolean = {
+        return result == 10;
+    }
+
+    return innerBenchmarkLoop(1){benchmark}{verifyResult};
+}
+
+def main() = {
+    List(0);
+}