Luabind

Luabind is a library that helps you create bindings between C++ and Lua. It has the ability to expose functions and classes, written in C++, to Lua. It will also supply the functionality to define classes in lua and let them derive from other lua classes or C++ classes. Lua classes can override virtual functions from their C++ baseclasses. It is written towards Lua 5.x, and does not work with Lua 4.

It is implemented utilizing template meta programming. That means that you don't need an extra preprocess pass to compile your project (it is done by the compiler). It also means you don't (usually) have to know the exact signature of each function you register, since the library will generate code depending on the compile-time type of the function (which includes the signature). The main drawback of this approach is that the compilation time will increase for the file that does the registration, it is therefore recommended that you register everything in the same cpp-file.

Luabind is released under the terms of the MIT license.

Copyright Daniel Wallin, Arvid Norberg 2003. Extracted from http://www.rasterbar.com/products/luabind/docs.html

This fork

I forked the project since it seems abandoned (latest commit from January 2012 on the 0.9 branch) and I ran into certain bugs which needed fixing (see commits).

This should actually have been forked from rpavlik/luabind: I cherry-picked most commits from there. Additionally, many commits from fhoefler/luaponte are incorporated (as the are in rpavlik's fork). Thus, feel free to do the same with my fork.

In the following two sections, the improvements over the latest official luabind release (0.9) are described.

Fixed bugs

• Destroyed objects now have their metatable unset. Previously, one could easily cause segmentation faults and other undefined behavior by accessing destroyed objects from luabinds __finalize or Lua 5.2's __gc. Now you can simply check with getmetatable(obj), and if you forget, you get an ordinary, well defined Lua error instead. Commit a83aa.

• The Lua part of a wrap_base derived class randomly got lost after a few garbage collection cycles due to errors in the implementation of the internal weak_ref class. Credits for the fix go to Max McGuire who posted a fix on luabind-user in 2010. Commit a3a400.

• The error message displayed when a function could not be called from Lua with the provided arguments sometimes only contained the function signatures but not the actual error message. mrwonko's commit 9d15e0 (and previous).

• Luabind did not work over shared library (DLL) boundaries on some platforms. fhoefling's commit a83af3 and my minor improvement a8349d.

• Calling call_function with a return type but not using it resulted in a call to std::terminate if the called function produced an error and a C++11 compliant compiler is used. Commit 81bdcb.

• Luabind failed to recognize Lua numbers correctly on MSVC x64. Commit c9582c.

• Luabind failed to compile on g++ with Boost 1.49 (BOOST_PP_ITERATION_FLAGS problem). The first one I know to have fixed this is fhoefling. Commit 1aa80b.

• Luabind failed to compile on Clang. Commit 4555b2.

Added features

• CMake replaces the broken Jamfile as build system (including installation and test support). A FindLuabind.cmake file is also provided, as well as FindLua52.cmake.
• A bit of C++11 support:
  • std::shared_ptr is supported as smart pointer through luabind/std_shared_ptr_converter.hpp. Commit 118f80.
  • Scoped enums can be used with enum_.
  • Basic rvalue reference support. fhoefling's commit a83af3.
  • Support for long long. Commit c9582c (also for pre-C++11 compilers supporting it).
• A new (C++) function set_package_preload can be used to register a (loader) function to be called only if it is required from Lua. rpavlik's commit 3502e9.
• Modules can now register everything to arbitrary tables (luabind::objects). fhoefling's commit dd4a16. This plays together very nicely with set_package_preload.
• The modulo operator % can now be exported to Lua. rpavlik's commit 855b4a and the following.
• class_info can now handle actual classes as arguments. Previously it could handle only objects of luabind classes. rpavlik's commit c2ee1f.

Additionally, the removal of many lines of death code, also unused (parts of) member variables and other minor improvements make luabind generally (a little bit) faster and less memory hungry.

Many compiler warnings have also been fixed. The remaining (irrelevant) ones are silenced, so the build should be completely warning- (and of course error-)free on Clang, g++ and MSVC.

This fork is fully source (API) compatible to the original luabind library, but not binary compatible.

A word on the branch names

First I worked against the 0.9 branch but then decided to rename it to master, since it actually has become the master branch of development in this fork. The original master branch is now named old-master.