functional list benchmark and part of rewrite of type info codegen for performance reasons

examples/src/benchmarks/FList.java

@@ -0,0 +1,86 @@
+import java.util.NoSuchElementException;
+
+abstract public class FList<T> {
+    abstract T getHead();
+
+    abstract FList<T> getTail();
+    
+    abstract FList<T> plus(T element);
+    
+    static class Empty<T> extends FList<T> {
+
+        @Override
+        T getHead() {
+            throw new NoSuchElementException();
+        }
+
+        @Override
+        FList<T> getTail() {
+            throw new NoSuchElementException();
+        }
+
+        @Override
+        FList<T> plus(T element) {
+            return new OneElementList<T>(element);
+        }
+    }
+
+    static class OneElementList<T> extends FList<T> {
+        private T element;
+
+        public OneElementList(T element) {
+            super();
+            this.element = element;
+        }
+
+        @Override
+        T getHead() {
+            return element;
+        }
+
+        @Override
+        FList<T> getTail() {
+            return new Empty<T>();
+        }
+
+        @Override
+        FList<T> plus(T element) {
+            return new StandardList<T>(element, this);
+        }
+    }
+
+    private static class StandardList<T> extends FList<T> {
+        private T head;
+        private FList<T> tail;
+
+        public StandardList(T head, FList<T> tail) {
+            this.head = head;
+            this.tail = tail;
+        }
+
+        @Override
+        T getHead() {
+            return head;
+        }
+
+        @Override
+        FList<T> getTail() {
+            return tail;
+        }
+
+        @Override
+        FList<T> plus(T element) {
+            return new StandardList<T>(element, this);
+        }
+    }
+
+    public static void main(String[] args) {
+        for(int k = 0; k != 10; ++k) {
+            long start = System.currentTimeMillis();
+            FList<Integer> list = new Empty();
+            for(int i = 0; i != 5000000; ++i)
+                list = list.plus(i);
+            System.out.println(System.currentTimeMillis()-start);
+        }
+    }
+}

examples/src/benchmarks/FList.kt

@@ -0,0 +1,70 @@
+namespace flist
+
+abstract class FList<T> {
+    abstract val head : T
+    abstract val tail : FList<T>
+
+    abstract fun plus(element: T) : FList<T>
+}
+
+class EmptyFList<T>() : FList<T> {
+    override val head: T
+        get() = throw java.util.NoSuchElementException()
+
+    override val tail : EmptyFList<T>
+        get() = EmptyFList<T>()
+
+    override fun plus(element: T) : FList<T> = OneElementFList<T>(element)
+}
+
+class OneElementFList<T> (override val head: T): FList<T> {
+    override val tail : EmptyFList<T>
+        get() = EmptyFList<T>()
+
+    override fun plus(element: T) : FList<T> = StandardFList<T>(element, this)
+}
+
+class StandardFList<T> (override val head: T, override val tail: FList<T>) : FList<T> {
+    override fun plus(element: T) : FList<T> = StandardFList<T>(element, this)
+}
+
+fun <T> FList<T>.plus2(element: T): FList<T> =
+    when(this) {
+        is EmptyFList<T> => OneElementFList<T>(element)
+        else => StandardFList<T>(element, this)
+    }
+
+fun <T> FList<T>.plus3(element: T) : FList<T> =
+    if(this is EmptyFList<*>)
+        OneElementFList<T>(element)
+    else
+        StandardFList<T>(element, this)
+
+fun main(args: Array<String>) {
+    for(k in 0..3) {
+        val start0 = System.currentTimeMillis()
+
+        var flist0 : FList<Int> = EmptyFList<Int>()
+        for(i in 0..5000000)
+        flist0 = flist0 + i
+
+        System.out?.println(System.currentTimeMillis() - start0)
+
+        val start = System.currentTimeMillis()
+
+        var flist : FList<Int> = EmptyFList<Int>()
+        for(i in 0..5000000)
+        flist = flist.plus2(i)
+
+        System.out?.println(System.currentTimeMillis() - start)
+
+        val start2 = System.currentTimeMillis()
+
+        var flist2 : FList<Int> = EmptyFList<Int>()
+        for(i in 0..5000000)
+        flist2 = flist2.plus3(i)
+
+        System.out?.println(System.currentTimeMillis() - start2)
+        System.out?.println()
+    }
+}