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Coding Standards
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OutputIterator
An output iterator is an iterator that can write a sequence of values. It is single-pass (old values of the iterator cannot be re-used), and write-only.
An output iterator represents a position in a (possibly infinite) sequence. Therefore, the iterator can point into the sequence (returning a value when dereferenced and being incrementable), or be off-the-end (and not dereferenceable or incrementable).
value_type
std::iterator_traits<Iter>::value_type
The stated value type of the iterator (should be void for an output iterator that does not model some other iterator concept).
difference_type
std::iterator_traits<Iter>::difference_type
The difference type of the iterator
category
std::iterator_traits<Iter>::iterator_category
The category of the iterator
The type Iter must be a model of Assignable.
The type ValueType must be a model of Assignable.
The type Iter must be a model of DefaultConstructible.
The type Iter must be a model of EqualityComparable.
category must be derived from std::output_iterator_tag, a model of DefaultConstructible, and a model of CopyConstructible.
difference_type must be a model of SignedInteger.
Name | Expression | Type | Precondition | Semantics | Postcondition |
---|---|---|---|---|---|
Dereference | *i | i is incrementable (not off-the-end) | |||
Dereference and assign | *i = x | i is incrementable (not off-the-end) | *i may not be written to again until it has been incremented. | ||
Preincrement | ++i | Iter & | i is incrementable (not off-the-end) | ||
Postincrement | i++ | i is incrementable (not off-the-end) | Equivalent to (void)(++i) | i is dereferenceable or off-the-end | |
Postincrement, dereference, and assign | *i++ = x | i is incrementable (not off-the-end) | Equivalent to {*i = t; ++i;} | i is dereferenceable or off-the-end |
All iterator operations must take amortized constant time.
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