embedded Lua loading modules programmatically (C++)

Question

I am embedding Lua in a C++ application.

I have some modules (for now, simple .lua scripts) that I want to load programmatically, as the engine is being started, so that when the engine starts, the module(s) is/are available to scripts without them having to include a require 'xxx' at the top of the script.

In order to do this, I need to be able to programmatically (i.e. C++ end), ask the engine to load the modules, as part of the initialisation (or shortly thereafter).

Anyone knows how I can do this?

snogglethorpe snogglethorpe · Accepted Answer · 2011-10-28T20:26:57

Hmm, I just use the simple approach: My C++ code just calls Lua's require function to pre-load the Lua scripts I want preloaded!

// funky = require ("funky")
//
lua_getfield (L, LUA_GLOBALSINDEX, "require"); // function
lua_pushstring (L, "funky");     // arg 0: module name
err = lua_pcall (L, 1, 1, 0);
// store funky module table in global var
lua_setfield (L, LUA_GLOBALSINDEX, "funky");

// ... later maybe handle a non-zero value of "err"
// (I actually use a helper function instead of lua_pcall
// that throws a C++ exception in the case of an error)

If you've got multiple modules to load, of course, put it in a loop... :)

embedded Lua loading modules programmatically (C++)

2 Answers