SWIG VS sol2

This sounds a bit like SWIG. You give SWIG an "interface file" describing the API of a library, and it uses that to spit out a bunch of language-specific bindings for that library.

Try out http://www.swig.org/

SWIG

Check out the site www.swig.org it will answer several of your questions. XS code is specific to Perl that you have to know how to code and use. SWIG takes code from C and C++ (actually several languages) and uses code templates to generate all the XS code for you. I wrote both a C library and C++ library doing different things, and used SWIG to import them into Perl (via "use"), Python and PHP. There is a learning curve, but it's not that bad, and there is a lot of great documentation and examples on the SWIG site.

Ohhh alrightt I went through the installation of pypodofo. 1. Install podofo library. For example in archlinux, pacman -S podofo 2. Install swig tool. Note, you should have installed gcc and g++ compilers 3. Build wrapper. python setup.py build 4. Copy dynamic library to python package. cp build/lib.linux-x86_64-3.7/_api.cpython-37m-x86_64-linux-gnu.so pypodofo/ 5. Install requirements. pip install -r requirements.txt (if possible in a virtualenv). 6. Run tests. nosetests tests/

Another option is SWIG, but I don't like it too much.

* I was using SWIG (http://www.swig.org/) 15+20 years ago to bind C/C++ to Perl and Java and it still exists.*

I've used it. It took the entire thing you want to call and generated one giant file of munged C. That's sort of where that idea takes you.

But the author is on to something. There's a C to Rust translator. It sucks, because it works by emulating C pointer arithmetic in unsafe Rust, using its own set of primitives along the lines of "offset this pointer by this much". Now you have ugly, unsafe Rust.

What's needed is something that infers the meaning of an ambiguous function call from the code. Something that reasons like this:

Function call:

    int read(char* buf, size_t n)

For the parsing part it is probably not a big deal. Either your own elisp code or use something like clangd. I am not so knowledgable about the implementation deatils for LSP & Co, but it is definitely possible to parse headers and extract definitions. There are also tools like swig.

Here is link number 2 - Previous text "Sol"

Sol for fast lua embedding

Have you considered using sol2? https://github.com/ThePhD/sol2 Or if you don't want to switch over, you can at least look at their code and see how they handle this.

It is half of a pun as I was inspired by [sol3](https://github.com/ThePhD/sol2) which is a lua c++ wrapper. Sol means sun and the julia c-api prefixes all it's functions with jl, luna means moon so it is pronounced "jay luna"

So far, it has been cumbersome to embed it into C-language projects, because it's C-interface is hard to use and poorly documented. Because of this, many choose to just use python or lua instead.

If you want to be portable I'd recommend C++ and Lua, I used those for years and it runs on everything and there's this most amazing wrapper API which was a huge inspiration

Off topic, but this is the author of my favourite Lua C++ binding library (https://github.com/ThePhD/sol2). Great guy!

I mean, if you could tell from my original post, I like C++ templates. The point is not to constantly write templates in your calling code, the point is to architect a library with templates that affords flexibility and dynamism so that the calling code is easy to write, read, and reason about. Consider, for example, the sol2[0] example usage code vs the actual source code itself[1].

0. https://github.com/ThePhD/sol2

Very interesting article!

Unfortunately, it doesn't mention Lua, which in my opinion has one of the most elegant C APIs that I have seen. It is entirely stack based, which means you only need to work with primitive types, such as numbers, C strings and user provided opaque pointers. As a consequence, you never have to care about memory management because Lua doesn't even let you access the actual Lua objects.

You want to create a table (= Lua's dictionary/array hybrid) and set a field "foo" to 5? lua_newtable() creates a new table and pushes it onto the stack. Then you push "foo" with lua_pushstring() and 5 with lua_pushnumber(). Finally you call lua_settable(), which pops the key and value from the stack, checks if the top of the stack contains a table, and if yes, sets the given field to the given value. The actual table structure is never exposed!

This kind of stack manipulation might seem unusual and a bit unweildy, but what you get is safety. If you mess up the stack or perform illegal operations, Lua will call an error handler, but the VM should never crash. The stack API can be seen as the fundamental layer upon which people can create nice abstractions for their host language of choice. Examples are "sol2" for C++ (https://github.com/ThePhD/sol2) or "lupa" for Python (https://github.com/scoder/lupa)

The public API is contained in "lua.h": https://github.com/lua/lua/blob/master/lua.h. "lauxlib.h" offers some useful helper functions: https://github.com/lua/lua/blob/master/lauxlib.h

For comparison, this is Python's "Limited" C API: https://docs.python.org/3/c-api/stable.html#stable

If you want to learn more about Lua's C API, have a look at section 4 in https://www.lua.org/manual/5.4/manual.html

Next to some already said examples: sol2 v3.0 https://github.com/ThePhD/sol2 - a Lua to C++ "header only" bridge...