orgstruct-heading-prefix-regexp is a variable defined in `org.el'.
Its value is
""
This variable is safe as a file local variable if its value
satisfies the predicate `stringp'.
Documentation:
Regexp that matches the custom prefix of Org headlines in
orgstruct(++)-mode.
You can customize this variable.
This variable was introduced, or its default value was changed, in
version 24.4 of Emacs.