1 files changed, 83 insertions, 0 deletions
diff --git a/src/include/iterator.H b/src/include/iterator.H
new file mode 100644
index 00000000..048dc67c
--- /dev/null
+++ b/src/include/iterator.H
@@ -0,0 +1,83 @@
+// -*- C++ -*-
+// Copyright (C) 2013, Gabriel Dos Reis.
+// All rights reserved.
+// Written by Gabriel Dos Reis.
+//
+// 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 OpenAxiom, 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.
+
+#ifndef OPENAXIOM_ITERATOR_included
+#define OPENAXIOM_ITERATOR_included
+
+#include <iterator>
+#include <open-axiom/defaults>
+#include "open-axiom.h"
+
+namespace OpenAxiom {
+   // -- Read-only iterator over a sequence with random access capabilities.
+   namespace iterator {
+      template<typename Seq>
+      struct basic
+         : std::iterator<std::random_access_iterator_tag,
+                         const typename Seq::value_type>,
+         defaults::neq<basic<Seq>>, defaults::ordering<basic<Seq>> {
+         using reference = typename Seq::const_reference;
+         using pointer = typename Seq::const_pointer;
+         using difference_type = typename Seq::difference_type;
+
+         reference operator*() const { return seq->at(idx); }
+         pointer operator->() const { return &seq->at(idx); }
+         reference operator[](Ordinal i) const { return seq->at(idx + i); }
+
+         basic& operator++() { ++idx; return *this; }
+         basic operator++(int) { auto t = *this; ++idx; return t; }
+         basic& operator--() { --idx; return *this; }
+         basic operator--(int) { auto t = *this; --idx; return t; }
+
+         basic& operator+=(Cardinal n) { idx += n; return *this; }
+         basic& operator-=(Cardinal n) { idx -= n; return *this; }
+         basic operator+(Cardinal n) const { return { seq, idx + n }; }
+         basic operator-(Cardinal n) const { return { seq, idx - n }; }
+         difference_type operator-(basic that) const { return idx - that.idx; }
+         
+
+         bool operator==(basic that) const { return idx == that.idx; }
+         bool operator<(basic that) const { return idx < that.idx; }
+         
+      private:
+         friend Seq;
+         const Seq* seq;
+         Ordinal idx;
+         constexpr basic(const Seq* s, Cardinal i) : seq(s), idx(i) { }
+      };
+   }
+}
+
+
+#endif  // OPENAXIOM_ITERATOR_included
+