tree changes

libs/lua/3rd/LuaBridge/detail/Iterator.h

@@ -0,0 +1,154 @@
+//------------------------------------------------------------------------------
+/*
+  https://github.com/vinniefalco/LuaBridge
+  
+  Copyright 2018, Dmitry Tarakanov
+  Copyright 2012, Vinnie Falco <vinnie.falco@gmail.com>
+
+  License: The MIT License (http://www.opensource.org/licenses/mit-license.php)
+
+  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.
+*/
+//==============================================================================
+
+#pragma once
+
+#include <LuaBridge/detail/LuaRef.h>
+
+#include <utility>
+
+
+namespace luabridge {
+
+/** Allows table iteration.
+*/
+class Iterator
+{
+  lua_State* m_L;
+  LuaRef m_table;
+  LuaRef m_key;
+  LuaRef m_value;
+
+  void next ()
+  {
+    m_table.push ();
+    m_key.push ();
+    if (lua_next (m_L, -2))
+    {
+      m_value.pop ();
+      m_key.pop ();
+    }
+    else
+    {
+      m_key = Nil ();
+      m_value = Nil ();
+    }
+    lua_pop (m_L, 1);
+  }
+
+public:
+  explicit Iterator (const LuaRef& table, bool isEnd = false)
+    : m_L (table.state ())
+    , m_table (table)
+    , m_key (table.state ()) // m_key is nil
+    , m_value (table.state ()) // m_value is nil
+  {
+    if (!isEnd)
+    {
+      next (); // get the first (key, value) pair from table
+    }
+  }
+
+  lua_State* state () const
+  {
+    return m_L;
+  }
+
+  std::pair <LuaRef, LuaRef> operator* () const
+  {
+    return std::make_pair (m_key, m_value);
+  }
+
+  LuaRef operator-> () const
+  {
+    return m_value;
+  }
+
+  bool operator!= (const Iterator& rhs) const
+  {
+    assert (m_L == rhs.m_L);
+    return !m_table.rawequal (rhs.m_table) || !m_key.rawequal (rhs.m_key);
+  }
+
+  Iterator& operator++ ()
+  {
+    if (isNil ())
+    {
+      // if the iterator reaches the end, do nothing
+      return *this;
+    }
+    else
+    {
+      next ();
+      return *this;
+    }
+  }
+
+  bool isNil () const
+  {
+    return m_key.isNil ();
+  }
+
+  LuaRef key () const
+  {
+    return m_key;
+  }
+
+  LuaRef value () const
+  {
+    return m_value;
+  }
+
+private:
+  // Don't use postfix increment, it is less efficient
+  Iterator operator++ (int);
+};
+
+class Range
+{
+  Iterator m_begin;
+  Iterator m_end;
+
+public:
+  Range (const Iterator& begin, const Iterator& end)
+    : m_begin (begin)
+    , m_end (end)
+  {
+  }
+
+  const Iterator& begin () const { return m_begin; }
+  const Iterator& end () const { return m_end; }
+};
+
+inline Range pairs (const LuaRef& table)
+{
+  return Range (Iterator (table, false), Iterator (table, true));
+}
+
+} // namespace luabridge