Difference between revisions of "cpp/named req/RandomAccessIterator"
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The above rules imply that RandomAccessIterator also implements {{concept|LessThanComparable}}. | The above rules imply that RandomAccessIterator also implements {{concept|LessThanComparable}}. | ||
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| + | A {{tt|mutable RandomAccessiterator}} is a {{tt|BidirectionalIterator}} that additionally satisfies the {{concept|OutputIterator}} requirements. | ||
Revision as of 12:57, 26 September 2012
Template:cpp/concept/title Template:cpp/concept/navbar
A RandomAccessIterator is a Template:concept that can be moved to point to any element in constant time.
A standard pointer is an example of a type that satisfies this concept.
Requirements
In addition to the above requirement, for a type It to be an RandomAccessIterator, instances a, b, i, and r of It must:
| Expression | Return | Equivalent expression | Notes |
|---|---|---|---|
| r += n | It& | if(n>=0) while(n--) ++r; |
|
| i + n | It | It temp = i; return temp += n; |
|
| n + i | It | i + n | |
| r -= n | It& | return r += -n; | |
| i - n | It | It temp = i; return temp -= n; |
|
| n - i | It | i - n | |
| b - a | difference |
n |
returns n such that a+n==b
|
| i[n] | convertible to reference |
*(i + n) | |
| a < b | contextually convertible to bool | b - a > 0 | Strict total ordering relation:
|
| a > b | contextually convertible to bool | b < a | Total ordering relation opposite to a < b |
| a >= b | contextually convertible to bool | !(a < b) | |
| a <= b | contextually convertible to bool | !(a > b) |
Table Notes
Itis the type implementing this conceptTis the type std::iterator_traits<It>::value_typereferenceis the type std::iterator_traits<It>::referencedifferenceis the type std::iterator_traits<It>::difference_typei,a,bare objects of typeItorconst Itris a value of typeIt&nis an integer of typedifference
The above rules imply that RandomAccessIterator also implements Template:concept.
A mutable RandomAccessiterator is a BidirectionalIterator that additionally satisfies the Template:concept requirements.
