--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main/java/fj/parser/Result.java	Fri Mar 20 21:04:03 2015 +0900
@@ -0,0 +1,163 @@
+package fj.parser;
+
+import fj.F;
+import fj.F2;
+import static fj.Function.curry;
+
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+
+/**
+ * A parse result made up of a value (A) and the remainder of the parse input (I).
+ *
+ * @version %build.number%
+ */
+public final class Result<I, A> implements Iterable<A> {
+  private final I i;
+  private final A a;
+
+  private Result(final I i, final A a) {
+    this.i = i;
+    this.a = a;
+  }
+
+  /**
+   * The remainder of the parse input.
+   *
+   * @return The remainder of the parse input.
+   */
+  public I rest() {
+    return i;
+  }
+
+  /**
+   * The parsed value.
+   *
+   * @return The parsed value.
+   */
+  public A value() {
+    return a;
+  }
+
+  /**
+   * Maps the given function across the remainder of the parse input.
+   *
+   * @param f The function to map with.
+   * @return A result with a different parse input.
+   */
+  public <J> Result<J, A> mapRest(final F<I, J> f) {
+    return result(f.f(i), a);
+  }
+
+  /**
+   * First-class function mapping across the remainder of the parse input.
+   *
+   * @return A first-class function mapping across the remainder of the parse input.
+   */
+  public <J> F<F<I, J>, Result<J, A>> mapRest() {
+    return new F<F<I, J>, Result<J, A>>() {
+      public Result<J, A> f(final F<I, J> f) {
+        return mapRest(f);
+      }
+    };
+  }
+
+  /**
+   * Maps the given function across the parse value.
+   *
+   * @param f The function to map with.
+   * @return A result with a different parse value.
+   */
+  public <B> Result<I, B> mapValue(final F<A, B> f) {
+    return result(i, f.f(a));
+  }
+
+  /**
+   * First-class function mapping across the parse value.
+   *
+   * @return A first-class function mapping across the parse value.
+   */
+  public <B> F<F<A, B>, Result<I, B>> mapValue() {
+    return new F<F<A, B>, Result<I, B>>() {
+      public Result<I, B> f(final F<A, B> f) {
+        return mapValue(f);
+      }
+    };
+  }
+
+  /**
+   * A bifunctor map across both the remainder of the parse input and the parse value.
+   *
+   * @param f The function to map the remainder of the parse input with.
+   * @param g The function to map the parse value with.
+   * @return A result with a different parse input and parse value.
+   */
+  public <B, J> Result<J, B> bimap(final F<I, J> f, final F<A, B> g) {
+    return mapRest(f).mapValue(g);
+  }
+
+  /**
+   * First-class bifunctor map.
+   *
+   * @return A first-class bifunctor map.
+   */
+  public <B, J> F<F<I, J>, F<F<A, B>, Result<J, B>>> bimap() {
+    return curry(new F2<F<I, J>, F<A, B>, Result<J, B>>() {
+      public Result<J, B> f(final F<I, J> f, final F<A, B> g) {
+        return bimap(f, g);
+      }
+    });
+  }
+
+  /**
+   * Returns an iterator over the parse value. This method exists to permit the use in a <code>for</code>-each loop.
+   *
+   * @return An iterator over the parse value.
+   */
+  public Iterator<A> iterator() {
+    return new Iterator<A>() {
+      private boolean r;
+
+      public boolean hasNext() {
+        return !r;
+      }
+
+      public A next() {
+        if (r)
+          throw new NoSuchElementException();
+        else {
+          r = true;
+          return a;
+        }
+      }
+
+      public void remove() {
+        throw new UnsupportedOperationException();
+      }
+    };
+  }
+
+  /**
+   * Construct a result with the given remainder of the parse input and parse value.
+   *
+   * @param i The remainder of the parse input.
+   * @param a The parse value.
+   * @return A result with the given remainder of the parse input and parse value.
+   */
+  public static <A, I> Result<I, A> result(final I i, final A a) {
+    return new Result<I, A>(i, a);
+  }
+
+  /**
+   * First-class construction of a result.
+   *
+   * @return A first-class function for construction of a result.
+   */
+  public static <A, I> F<I, F<A, Result<I, A>>> result() {
+    return curry(new F2<I, A, Result<I, A>>() {
+      public Result<I, A> f(final I i, final A a) {
+        return result(i, a);
+      }
+    });
+  }
+}