 
 
 
|  |  | 
| Category: containers | Component type: concept | 
| Key type | X::key_type | The type of the key associated with X::value_type. The types key_type and value_type must be the same type. | 
| Iterator | X::iterator | 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. [1] | 
| X | A type that is a model of Simple Associative Container | 
| a | Object of type X | 
| k | Object of type X::key_type | 
| p, q | Object of type X::iterator | 
| Immutability of Elements | Every element of a Simple Associative Container is immutable. Objects may be inserted and erased, but not modified. [1] | 
[1] This is a consequence of the Immutability of Keys invariant of Associative Container. Keys may never be modified; values in a Simple Associative Container are themselves keys, so it immediately follows that values in a Simple Associative Container may not be modified.
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