None, except for those described in the Associative Container requirements. Simple Associative Container, however, introduces two new type restrictions.
||The type of the key associated with X::value_type. The types key_type and value_type must be the same type.|
||The type of iterator used to iterate through a Simple Associative Container's elements. The types X::iterator and X::const_iterator must be the same type. That is, a Simple Associative Container does not provide mutable iterators. |