Make lpeg an optional dependency

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "thirdparty/LuLPeg"]
+	path = thirdparty/LuLPeg
+	url = https://github.com/pygy/LuLPeg

README.md

@@ -8,8 +8,13 @@ interfaces, and modules.
 # Requirements for running the compiler
 
     lua >= 5.1
+
+## Optional Requirements
+
     lpeg >= 0.12
 
+If lpeg is not found via `require "lpeg"`, then [LuLPeg](https://github.com/pygy/LuLPeg) will be used instead.
+
 # Usage
 
     $ tlc [options] [filename]
@@ -23,6 +28,10 @@ interfaces, and modules.
     -p	    print the AST
     -v	    print current version
 
+# Checkout
+
+	git clone --recursive https://github.com/andremm/typedlua
+
 # License
 
 Released under the MIT License (MIT)

typedlua/tllexer.lua

@@ -4,7 +4,8 @@ This module implements Typed Lua lexer
 
 local tllexer = {}
 
-local lpeg = require "lpeg"
+local success, lpeg = pcall(require, "lpeg")
+lpeg = success and lpeg or require "thirdparty/lulpeg/lulpeg":register(not _ENV and _G)
 lpeg.locale(lpeg)
 
 local function getffp (s, i, t)

typedlua/tlparser.lua

@@ -4,7 +4,8 @@ This module implements Typed Lua parser
 
 local tlparser = {}
 
-local lpeg = require "lpeg"
+local success, lpeg = pcall(require, "lpeg")
+lpeg = success and lpeg or require "thirdparty/lulpeg/lulpeg":register(not _ENV and _G)
 lpeg.locale(lpeg)
 
 local tlast = require "typedlua.tlast"