1 files changed, 20 insertions, 0 deletions
diff --git a/test/undefined.lua b/test/undefined.lua
new file mode 100644
index 00000000..bbecffe3
--- /dev/null
+++ b/test/undefined.lua
@@ -0,0 +1,20 @@
+-- catch "undefined" global variables. see FAQ.
+
+do
+ local f=function(name)
+  local v=rawget(globals(),name)
+  if v then
+   return v
+  else
+   error("undefined global variable `"..name.."'")
+  end
+ end
+
+ settagmethod(tag(nil),"getglobal",f)
+end
+
+-- an example
+
+a=1
+c=3
+print(a,b,c)	-- 'b' is undefined