lua-procure - A Pure Lua Implementation of require()

This library is a pure Lua implementation of require(). It exists as a reference for people experienced in Lua but not C and would like a code-based way of looking at how require() hows. However, that isn't the only purpose of this library; I intend to deliver more advanced features on top of the basic require() functionality.

For more information, see this thread on the Lua mailing list:

http://lua-users.org/lists/lua-l/2012-08/msg00207.html

Usage

If you want to try this library out, all you need to do is this:

local require = require 'procure'

And require() statements in the current chunk will use the pure Lua variant. If you're feeling dangerous, you could always override the global one:

_G.require = require 'procure'

Additional Methods/Functions

In addition to the require() functionality that this library supports, it also supports other methods and functions related to loading libraries.

procure.findchunk(name)

This function finds the code chunk that require itself would load and returns it. If no library is found with the name name, nil and an error message are returned. An example usage for this would be to load plugins for a program; you want to use require's loaders to find a plugin, but you want to be able to run them in a custom environment.

procure.isolated(name)

This function behaves exactly like procure(), except the module specified by name is loaded in an isolated environment (it cannot make changes to the global environment). This is to allow users who want to keep a clean global environment to use modules that "misbehave" in this regard.

It's not entirely impossible for isolated modules to alter the global environment; while naïve global assignment (assigning to a variable not declared with local) and assigning to _G will be intercepted, assigning to keys in the value returned by getfenv(0) (for example) will not. I feel this is a proper balance between cleanliness and flexibility.