| hash-table | System Class |
Hash tables provide a way of mapping any object (a key) to an associated object (a value).
Section 18.1 (Hash Table Concepts), Section 22.1.3.13 (Printing Other Objects)
The intent is that this mapping be implemented by a hashing mechanism, such as that described in Section 6.4 “Hashing” of The Art of Computer Programming, Volume 3 (pp506-549). In spite of this intent, no conforming implementation is required to use any particular technique to implement the mapping.