README.md in cloudformation-ruby-dsl-1.4.1 vs README.md in cloudformation-ruby-dsl-1.4.2

- old
+ new

@@ -92,9 +92,11 @@
 - `get_azs(region)`
 - `join(delim, *list)`
 - `select(index, list)`
 - `ref(name)`
 - `import_value(value)`
+- `sub(sub_string)`
+- `sub(sub_string, var_map)`
 
 Intrinsic conditionals are also supported, with some syntactic sugar.
 - `fn_not(condition)`
 - `fn_or(*condition_list)`
 - `fn_and(*condition_list)`