Input IteratorAn Input Iterator is a Trivial Iterator that provides a way to obtain the next iterator in a sequence.
i is incrementable if there is a "next" iterator, that is, if i::next expression is well-defined; past-the-end iterators are not incrementable;
j is reachable from a forward iterator i if, after recursive application of next operation to i a finite number of times, i is identical to j;
[i,j) refers to a range of iterators beginning with i and up to but not including j;
[i,j) is a valid range if both i and j are valid iterators, and j is reachable from i.
In addition to the expressions defined in Trivial Iterator, the following expressions must be valid.
| Expression | Expression type |
|---|---|
typename i::next | A model of Input Iterator |
| Expression | Complexity | Precondition | Semantics | Postcondition |
|---|---|---|---|---|
typename i::next | Amortized constant time | i is incrementable | i::next is the next iterator in a sequence | i::next is dereferenceable or past-the-end |
Sequence, Trivial Iterator, Forward Iterator