From acdb58a44792582427a94c51a3d3f4f6afe79003 Mon Sep 17 00:00:00 2001
From: rxi <rxi@users.noreply.github.com>
Date: Sat, 5 Apr 2014 14:41:31 +0100
Subject: [PATCH] Added lume.uuid(), tests and README.md section

---
 README.md          |  4 ++++
 lume.lua           | 11 +++++++++++
 test/test_lume.lua |  6 ++++++
 3 files changed, 21 insertions(+)

diff --git a/README.md b/README.md
index 4239ffc..26aaeeb 100644
--- a/README.md
+++ b/README.md
@@ -291,6 +291,10 @@ Executes the lua code inside `str`.
 lume.dostring("print('Hello!')") -- Prints "Hello!"
 ```
 
+### lume.uuid()
+Generates a random UUID string; version 4 as specified in
+[RFC 4122](http://www.ietf.org/rfc/rfc4122.txt).
+
 ### lume.hotswap(modname)
 Reloads an already loaded module in place, allowing you to immediately see the
 effects of code changes without having to restart the program. `modname` should
diff --git a/lume.lua b/lume.lua
index 191ef13..b2e4109 100644
--- a/lume.lua
+++ b/lume.lua
@@ -361,6 +361,17 @@ function lume.dostring(str)
 end
 
 
+function lume.uuid()
+  local hex = "0123456789abcdef"
+  local fn = function(x)
+    local r = math.random(16) - 1
+    r = (x == "x") and (r + 1) or (r % 4) + 9
+    return hex:sub(r, r)
+  end
+  return (("xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx"):gsub("[xy]", fn))
+end
+
+
 function lume.hotswap(modname)
   local oldglobal = lume.clone(_G)
   local updated = {}
diff --git a/test/test_lume.lua b/test/test_lume.lua
index eb88a19..97cac16 100644
--- a/test/test_lume.lua
+++ b/test/test_lume.lua
@@ -371,6 +371,12 @@ tests["lume.dostring"] = function()
   testeq( lume.dostring([[return 12345]]),    12345     )   
 end
 
+
+tests["lume.uuid"] = function()
+  testeq( type(lume.uuid()), "string" )
+  testeq( #lume.uuid(),      36       )
+end
+
 -- lume.hotswap
 tests["lume.hotswap"] = function()
   local ok, err = lume.hotswap("bad_module_name")