From b61d233ac2a1d30a38bc56d54e602a9653fb6b4a Mon Sep 17 00:00:00 2001
From: Peter Colberg <peter.colberg@utoronto.ca>
Date: Wed, 21 Dec 2011 12:37:51 -0500
Subject: [PATCH] Lua 5.2: replace lua_equal and lua_lessthan with lua_compare

http://www.lua.org/manual/5.2/manual.html#8.3

http://www.lua.org/manual/5.2/manual.html#lua_compare
---
 doc/docs.rst         |  2 +-
 luabind/object.hpp   | 20 ++++++++++++++++----
 src/create_class.cpp |  9 +++++++--
 3 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/doc/docs.rst b/doc/docs.rst
index d9543a6..61a1bce 100755
--- a/doc/docs.rst
+++ b/doc/docs.rst
@@ -1116,7 +1116,7 @@ The ``interpreter()`` function returns the Lua state where this object is stored
 If you want to manipulate the object with Lua functions directly you can push
 it onto the Lua stack by calling ``push()``.
 
-The operator== will call lua_equal() on the operands and return its result.
+The operator== will call lua_compare() on the operands and return its result.
 
 The ``is_valid()`` function tells you whether the object has been initialized
 or not. When created with its default constructor, objects are invalid. To make
diff --git a/luabind/object.hpp b/luabind/object.hpp
index f7b7ca5..106c2e2 100644
--- a/luabind/object.hpp
+++ b/luabind/object.hpp
@@ -45,6 +45,12 @@
 #include <boost/preprocessor/iteration/iterate.hpp>
 #include <boost/utility/enable_if.hpp>
 
+#if LUA_VERSION_NUM < 502
+# define lua_compare(L, index1, index2, fn) fn(L, index1, index2)
+# define LUA_OPEQ lua_equal
+# define LUA_OPLT lua_lessthan
+#endif
+
 namespace luabind {
 
 namespace detail 
@@ -208,11 +214,11 @@
       detail::stack_pop pop2(L, 1); \
       detail::push(L, rhs); \
 \
-      return fn(L, -1, -2) != 0; \
+      return lua_compare(L, -1, -2, fn) != 0; \
   }
 
-LUABIND_BINARY_OP_DEF(==, lua_equal)
-LUABIND_BINARY_OP_DEF(<, lua_lessthan)
+LUABIND_BINARY_OP_DEF(==, LUA_OPEQ)
+LUABIND_BINARY_OP_DEF(<, LUA_OPLT)
 
   template<class ValueWrapper>
   std::ostream& operator<<(std::ostream& os
@@ -523,7 +529,7 @@
           detail::stack_pop pop(m_interpreter, 2);
           m_key.push(m_interpreter);
           other.m_key.push(m_interpreter);
-          return lua_equal(m_interpreter, -2, -1) != 0;
+          return lua_compare(m_interpreter, -2, -1, LUA_OPEQ) != 0;
       }
 
       adl::iterator_proxy<AccessPolicy> dereference() const 
@@ -1406,5 +1412,11 @@ object property(GetValueWrapper const& get, SetValueWrapper const& set)
 
 } // namespace luabind
 
+#if LUA_VERSION_NUM < 502
+# undef lua_compare
+# undef LUA_OPEQ
+# undef LUA_OPLT
+#endif
+
 #endif // LUABIND_OBJECT_050419_HPP
 
diff --git a/src/create_class.cpp b/src/create_class.cpp
index c0eb719..9800c15 100755
--- a/src/create_class.cpp
+++ b/src/create_class.cpp
@@ -26,6 +26,11 @@
 
 #include <luabind/luabind.hpp>
 
+#if LUA_VERSION_NUM < 502
+# define lua_compare(L, index1, index2, fn) fn(L, index1, index2)
+# define LUA_OPEQ lua_equal
+#endif
+
 namespace luabind { namespace detail
 {
 	namespace
@@ -40,7 +45,7 @@
 			while (lua_next(L, -2))
 			{
 				lua_pushstring(L, "__init");
-				if (lua_equal(L, -1, -3))
+				if (lua_compare(L, -1, -3, LUA_OPEQ))
 				{
 					lua_pop(L, 2);
 					continue;
@@ -48,7 +53,7 @@
 				else lua_pop(L, 1); // __init string
 
 				lua_pushstring(L, "__finalize");
-				if (lua_equal(L, -1, -3))
+				if (lua_compare(L, -1, -3, LUA_OPEQ))
 				{
 					lua_pop(L, 2);
 					continue;
-- 
1.8.1.6