--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nashorn/samples/fixed_point.js	Fri Sep 04 17:11:06 2015 +0530
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   - Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *
+ *   - Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *
+ *   - Neither the name of Oracle nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+// Simple sample demonstrating "fixed point" computation with Streams
+
+// See also https://mitpress.mit.edu/sicp/chapter1/node21.html#secprocgeneralmethods
+var Stream = Java.type("java.util.stream.Stream");
+
+// generic fixed point procedure
+function fixed_point(f, init_guess) {
+  var tolerance = 0.00001;
+  function close_enough(v1, v2) Math.abs(v1 - v2) < tolerance;
+ 
+  var prev; 
+  return Stream.iterate(init_guess, f)
+      .filter(function(x) {
+          try {
+              return prev == undefined? false : close_enough(prev, x);
+          } finally {
+              prev = x;
+          }
+      })
+      .findFirst()
+      .get();
+}
+
+// solution to x = cos(x)
+print(fixed_point(Math.cos, 1.0))
+
+// solution to x = sin(x) + cos(x)
+print(fixed_point(function(x) Math.sin(x) + Math.cos(x), 1.0));
+
+// square root by Newton's method
+// http://en.wikipedia.org/wiki/Newton's_method
+function sqrt(n)
+  fixed_point(function(x) (x + n/x) / 2, 2.0);
+
+print(sqrt(2))
+print(sqrt(3))
+
+