Modules

[liquidev]

One thing that's nice about Lua is it's very simplistic module system. Basically, each file is treated like a function, and can return any arbitrary value as a result:

-- my_module.lua
local my_module = {}

function my_module.hello()
  print("yo!")
end

return my_module

Then, one can import the module by using the require function, which searches for modules relative to the main module.

-- main.lua
local my_module = require "my_module"
my_module.hello()

However, I see a few problems with this. The most important one is that libraries need to implement weird hacks to get relative requires, which is not ideal. Ruby solves this by having a separate require_relative, but I think it looks quite ugly.

The basics: require in Mica

require would work the same way it does in Lua. The value returned by the module is also returned by require.

# my_module.mi
impl struct MyModule # see #54
  func hello()
    print("yo!")
  end
end

MyModule

# main.mi
MyModule = require("./my_module")
MyModule.hello()

Unlike Lua however, require works more like in Node.js, where paths use / as a path separator, and if a path doesn't start with . or .., a system module is loaded. System modules are provided by the standard library and host application; for instance, NetCanv could register a module netcanv.

netcanv = require("netcanv")  # require a system module
brush = require("netcanv/brush")  # system modules can have submodules
util = require("./util")  # require a local module