WIP define expected usage of IterSouce

src/lib/iter-source.hpp

@@ -0,0 +1,73 @@
+/*
+  ITER-SOURCE.hpp  -  an interface to build an opaque iterator-based data source 
+ 
+  Copyright (C)         Lumiera.org
+    2010,               Hermann Vosseler <Ichthyostega@web.de>
+ 
+  This program is free software; you can redistribute it and/or
+  modify it under the terms of the GNU General Public License as
+  published by the Free Software Foundation; either version 2 of the
+  License, or (at your option) any later version.
+ 
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+ 
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ 
+*/
+
+/** @file iter-source.hpp
+ ** Extension module to build an opaque data source, accessible as
+ ** <i>Lumiera Forward Iterator</i>. It is based on combining an IterAdapter
+ ** with classical polymorphism; here, the data source, which is addressed
+ ** by IderAdapter through the "iteration control API", is abstracted behind
+ ** an interface (with virtual functions). Together this allows to build
+ ** a simple data source type, without needing to disclose details of
+ ** the implementation.
+ ** 
+ ** @see iter-adapter.hpp
+ ** @see itertool.hpp
+ ** @see iter-source-test.cpp
+ ** 
+ */
+
+
+#ifndef LIB_ITER_SOURCE_H
+#define LIB_ITER_SOURCE_H
+
+
+#include "lib/iter-adapter.hpp"
+//#include "lib/bool-checkable.hpp"
+
+
+
+
+namespace lib {
+  
+  
+  namespace {
+  }
+  
+  
+  /**
+   * Iteration source interface to abstract a data source,
+   * which then can be accessed through IterAdapter as a frontend,
+   * allowing to pull individual elements until exhaustion.
+   * 
+   * @see PlacementIndex::Table#_eachEntry_4check usage example
+   * @see iter-source-test.cpp
+   */
+  template<class TY>
+  class IterSource
+    : public lib::BoolCheckable<IterSource<TY> >
+    {
+    };
+  
+  
+  
+} // namespace lib
+#endif

tests/lib/iter-source-test.cpp

@@ -0,0 +1,147 @@
+/*
+  IterSource(Test)  -  how to build an opaque iterator-based data source
+ 
+  Copyright (C)         Lumiera.org
+    2010,               Hermann Vosseler <Ichthyostega@web.de>
+ 
+  This program is free software; you can redistribute it and/or
+  modify it under the terms of the GNU General Public License as
+  published by the Free Software Foundation; either version 2 of the
+  License, or (at your option) any later version.
+ 
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+ 
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ 
+* *****************************************************/
+
+
+
+#include "lib/test/run.hpp"
+#include "lib/util.hpp"
+
+#include "lib/iter-source.hpp"
+
+#include <boost/lexical_cast.hpp>
+#include <iostream>
+#include <list>
+
+
+
+namespace lib {
+namespace test{
+  
+  using ::Test;
+  using boost::lexical_cast;
+  using util::isnil;
+  using std::list;
+  using std::cout;
+  using std::endl;
+  
+  
+  
+  namespace { // Subject of test
+    
+    
+    uint NUM_ELMS = 10;
+    
+    /** 
+     * Explicit implementation of the IterSource interface (test dummy)
+     */
+    class TestSource
+      : public IterSource<char*>
+      {
+      };
+    
+      
+    /** test dummy, simply wrapping an STL container
+     *  and exposing a range as Lumiera Forward Iterator
+     */
+    struct WrappedList
+      {
+        list<int> data_;
+        
+        WrappedList(uint num)
+          {
+            while (num)
+              data_.push_back(num--);
+          }
+        
+        typedef list<int>::iterator sourceIter;
+        typedef RangeIter<sourceIter> iterator;
+        
+        typedef list<int>::const_iterator const_sourceIter;
+        typedef RangeIter<const_sourceIter> const_iterator;
+        
+        iterator       begin()       { return       iterator(data_.begin(),data_.end()); }
+        iterator       end()         { return       iterator();                          }
+        const_iterator begin() const { return const_iterator(data_.begin(),data_.end()); }
+        const_iterator end()   const { return const_iterator();                          }
+        
+      };
+    
+  } // (END) impl test dummy containers
+  
+  
+  
+  
+  
+  
+  
+  /******************************************************************
+   *  @test create some (opaque) data sources,
+   *        and then pull the data out by iteration.
+   *        Demonstrates simple usage of the IterSource inteface
+   *        
+   */
+  class IterSource_test : public Test
+    {
+      
+      typedef IterSource<int>::iterator IntIter;
+      typedef IterSource<char*>::iterator StrIter;
+    
+      virtual void
+      run (Arg arg)
+        {
+          if (0 < arg.size()) NUM_ELMS = lexical_cast<uint> (arg[0]);
+          
+          // build the test data sources
+          WrappedList customList(NUM_ELMS);
+          TestSource dedicatedSource(NUM_ELMS);
+          
+          IntIter iii (eachEntry (customList));
+          StrIter cii (IterSource<char*>::build(dedicatedSource));
+          
+          ASSERT (!isnil (iii));
+          ASSERT (!isnil (cii));
+          
+          pullOut (iii);
+          pullOut (cii);
+          
+          ASSERT (!iii);
+          ASSERT (!cii);
+        }
+      
+      
+      
+      template<class IT>
+      void
+      pullOut (IT const& ii)
+        {
+          for (IT iter(ii) ; iter; ++iter )
+            cout << "::" << *iter;
+          cout << endl;
+        }
+      
+    };
+  
+  LAUNCHER (IterSource_test, "unit common");
+  
+  
+}} // namespace lib::test
+