Multiple definitions of main

how do I correctly implement Lua in a C++ program? I downloaded the Lua source, put the .c files in my src folder and the .h files in my include folder, included lua.h in my program's source code (with extern "C"{} of course) and hit "Build".

That's how all the tutorials tell me to use Lua with a C++ project.

But now I get the error "multiple definition of main" and some Symbo开发者_开发百科ls in the Lua code that could not be resolved. I understand what the first error means (conflict because Lua has a main and my program also has one), but how can I solve it?

Or did I understand something completely wrong about implementing Lua in a C++ program?

Check to make sure you didn't include luac.c, lua.c, and the source for any other programs that are included with Lua in with your source code. Lua's source includes a few extra utilities (i.e., luac), and chances are you've just included them in the project and forgotten to remove them, thus resulting in having more than one main.

In short, those are separate programs that you don't add to your project. If you can, just build Lua normally, link to the library, and include the header files as normal.

So, on the point of you misunderstanding how to use Lua, you probably did to some degree. It is entirely possible to just copy Lua's source into your code, though probably not advisable. What you really want to do is pull up the extracted Lua source in a terminal and build it. Then (according to Lua's INSTALL document), you'll want to type make platform, where you'll replace platform with whichever platform you're currently using (i.e., I'd use macosx, you might use linux, refer to the INSTALL for which platforms are supported). After that, it's up to you if you want to install it or not, but you'll just do make install (or sudo make install) to get that done.

After that, either add the appropriate linker flags when compiling to link to Lua (e.g., -llua) or alter your project's settings in your editor of choice to do roughly the same thing. That said, you'll want to refer to the INSTALL document provided with Lua for complete instructions on this.

I'm embedding Lua in my projects other way around, preferred way, IMO: compiled Lua as a static library.

Just comment the two main() blocks in Lua.c an Luac.c, then hit build and run again.

I made this on Lua 5.3.