bit of cleanup, few steps towards commands demo

examples/hello-world/main.orc

@@ -2,3 +2,8 @@ let user = r[ "foo" 1, "bar" t[3, 4] ]
 let _main = user.bar.1
 
 let main = "foo" + string::slice "hello" 1 3 + "bar"
+
+let io_main = (
+  stdio::get_stdout \stdout
+  -- TODO: missing output commands in std
+)