Diff: fixed_iterator.h

Revision:

0:b47c2a7920c2

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fixed_iterator.h	Fri Mar 16 16:34:18 2018 +0000
@@ -0,0 +1,271 @@
+///\file
+
+/******************************************************************************
+The MIT License(MIT)
+
+Embedded Template Library.
+https://github.com/ETLCPP/etl
+http://www.etlcpp.com
+
+Copyright(c) 2015 jwellbelove
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files(the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and / or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions :
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+******************************************************************************/
+
+#ifndef __ETL_FIXED_ITERATOR__
+#define __ETL_FIXED_ITERATOR__
+
+#include <iterator>
+
+#include "platform.h"
+
+///\defgroup iterator Iterator types
+
+namespace etl
+{
+  /// A fixed iterator class.
+  /// This iterator can be given an iterator value, which will not be allowed to be incremented or decremented.
+  /// This can be useful when using STL algorithms to interact with fixed memory locations such as registers.
+  ///\ingroup iterator
+  template <typename TIterator>
+  class fixed_iterator : std::iterator<typename std::iterator_traits<TIterator>::iterator_category, typename std::iterator_traits<TIterator>::value_type>
+  {
+  public:
+
+    //***************************************************************************
+    /// Default constructor.
+    //***************************************************************************
+    fixed_iterator()
+      : it(TIterator())
+    {
+    }
+
+    //***************************************************************************
+    /// Construct from iterator.
+    //***************************************************************************
+    fixed_iterator(TIterator it_)
+      : it(it_)
+    {
+    }
+
+    //***************************************************************************
+    /// Increment (Does nothing).
+    //***************************************************************************
+    fixed_iterator& operator ++()
+    {
+      return *this;
+    }
+
+    //***************************************************************************
+    /// Increment (Does nothing).
+    //***************************************************************************
+    fixed_iterator operator ++(int)
+    {
+      return *this;
+    }
+
+    //***************************************************************************
+    /// Decrement (Does nothing).
+    //***************************************************************************
+    fixed_iterator& operator --()
+    {
+      return *this;
+    }
+
+    //***************************************************************************
+    /// Decrement (Does nothing).
+    //***************************************************************************
+    fixed_iterator operator --(int)
+    {
+      return *this;
+    }
+
+    //***************************************************************************
+    /// Dereference operator.
+    //***************************************************************************
+    typename std::iterator_traits<TIterator>::value_type operator *()
+    {
+      return *it;
+    }
+
+    //***************************************************************************
+    /// Dereference operator.
+    //***************************************************************************
+    const typename std::iterator_traits<TIterator>::value_type operator *() const
+    {
+      return *it;
+    }
+
+    //***************************************************************************
+    /// -> operator.
+    //***************************************************************************
+    TIterator operator ->()
+    {
+      return it;
+    }
+
+    //***************************************************************************
+    /// -> operator.
+    //***************************************************************************
+    const TIterator operator ->() const
+    {
+      return it;
+    }
+
+    //***************************************************************************
+    /// Conversion operator.
+    //***************************************************************************
+    operator TIterator() const
+    {
+      return it;
+    }
+
+    //***************************************************************************
+    /// += operator.
+    //***************************************************************************
+    fixed_iterator& operator +=(typename std::iterator_traits<TIterator>::difference_type /*offset*/)
+    {
+      return *this;
+    }
+
+    //***************************************************************************
+    /// -= operator.
+    //***************************************************************************
+    fixed_iterator& operator -=(typename std::iterator_traits<TIterator>::difference_type /*offset*/)
+    {
+      return *this;
+    }
+
+    //***************************************************************************
+    /// Assignment from iterator.
+    //***************************************************************************
+    fixed_iterator& operator =(TIterator new_it)
+    {
+      it = new_it;
+      return *this;
+    }
+
+    //***************************************************************************
+    /// Assignment from fixed_iterator.
+    //***************************************************************************
+    fixed_iterator& operator =(fixed_iterator other)
+    {
+      it = other.it;
+      return *this;
+    }
+
+  private:
+
+    TIterator it; ///< The underlying iterator.
+  };
+}
+
+//*****************************************************************************
+/// + difference operator.
+//*****************************************************************************
+template <typename TIterator>
+etl::fixed_iterator<TIterator>& operator +(etl::fixed_iterator<TIterator>& lhs,
+                                           typename std::iterator_traits<TIterator>::difference_type /*rhs*/)
+{
+  return lhs;
+}
+
+//*****************************************************************************
+/// - difference operator.
+//*****************************************************************************
+template <typename TIterator>
+etl::fixed_iterator<TIterator>& operator -(etl::fixed_iterator<TIterator>& lhs,
+                                           typename std::iterator_traits<TIterator>::difference_type /*rhs*/)
+{
+  return lhs;
+}
+
+//*****************************************************************************
+/// - fixed_iterator operator.
+//*****************************************************************************
+template <typename TIterator>
+typename std::iterator_traits<TIterator>::difference_type operator -(etl::fixed_iterator<TIterator>& lhs,
+                                                                     etl::fixed_iterator<TIterator>& rhs)
+{
+  return TIterator(lhs) - TIterator(rhs);
+}
+
+//*****************************************************************************
+/// Equality operator. fixed_iterator == fixed_iterator.
+//*****************************************************************************
+template <typename TIterator>
+bool operator ==(const etl::fixed_iterator<TIterator>& lhs,
+                 const etl::fixed_iterator<TIterator>& rhs)
+{
+  return TIterator(lhs) == TIterator(rhs);
+}
+
+//*****************************************************************************
+/// Equality operator. fixed_iterator == iterator.
+//*****************************************************************************
+template <typename TIterator>
+bool operator ==(const etl::fixed_iterator<TIterator>& lhs,
+                 TIterator rhs)
+{
+  return TIterator(lhs) == rhs;
+}
+
+//*****************************************************************************
+/// Equality operator. iterator == fixed_iterator.
+//*****************************************************************************
+template <typename TIterator>
+bool operator ==(TIterator lhs,
+                 const etl::fixed_iterator<TIterator>& rhs)
+{
+  return lhs == TIterator(rhs);
+}
+
+
+//*****************************************************************************
+/// Inequality operator. fixed_iterator == fixed_iterator.
+//*****************************************************************************
+template <typename TIterator>
+bool operator !=(const etl::fixed_iterator<TIterator>& lhs,
+                 const etl::fixed_iterator<TIterator>& rhs)
+{
+  return !(lhs == rhs);
+}
+
+//*****************************************************************************
+/// Inequality operator. fixed_iterator == iterator.
+//*****************************************************************************
+template <typename TIterator>
+bool operator !=(const etl::fixed_iterator<TIterator>& lhs,
+                 TIterator rhs)
+{
+  return !(lhs == rhs);
+}
+
+//*****************************************************************************
+/// Inequality operator. iterator == fixed_iterator.
+//*****************************************************************************
+template <typename TIterator>
+bool operator !=(TIterator& lhs,
+                 const etl::fixed_iterator<TIterator>& rhs)
+{
+  return !(lhs == rhs);
+}
+
+#endif
+