[ceph.git] / ceph / src / boost / libs / range / doc / reference / algorithm / merge.qbk

[/
    Copyright 2010 Neil Groves
    Distributed under the Boost Software License, Version 1.0.
    (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
/]
[section:merge merge]

[heading Prototype]

``
template<
    class SinglePassRange1,
    class SinglePassRange2,
    class OutputIterator
    >
OutputIterator merge(const SinglePassRange1& rng1,
                     const SinglePassRange2& rng2,
                     OutputIterator          out);

template<
    class SinglePassRange1,
    class SinglePassRange2,
    class OutputIterator,
    class BinaryPredicate
    >
OutputIterator merge(const SinglePassRange1& rng1,
                     const SinglePassRange2& rng2,
                     OutputIterator          out,
                     BinaryPredicate         pred);
``

[heading Description]

`merge` combines two sorted ranges `rng1` and `rng2` into a single sorted range by copying elements. `merge` is stable. The return value is `out + distance(rng1) + distance(rng2)`.

The two versions of `merge` differ by how they compare the elements.

The non-predicate version uses the `operator<()` for the range value type. The predicate version uses the predicate instead of `operator<()`.

[heading Definition]

Defined in the header file `boost/range/algorithm/merge.hpp`

[heading Requirements]

[*For the non-predicate version:]

* `SinglePassRange1` is a model of the __single_pass_range__ Concept.
* `SinglePassRange2` is a model of the __single_pass_range__ Concept.
* `range_value<SinglePassRange1>::type` is the same as `range_value<SinglePassRange2>::type`.
* `range_value<SinglePassRange1>::type` is a model of the `LessThanComparableConcept`.
* The ordering on objects of `range_value<SinglePassRange1>::type` is a [*/strict weak ordering/], as defined in the `LessThanComparableConcept` requirements.
* `range_value<SinglePassRange1>::type` is convertible to a type in `OutputIterator`'s set of value types.

[*For the predicate version:]

* `SinglePassRange1` is a model of the __single_pass_range__ Concept.
* `SinglePassRange2` is a model of the __single_pass_range__ Concept.
* `range_value<SinglePassRange1>::type` is the same as `range_value<SinglePassRange2>::type`.
* `BinaryPredicate` is a model of the `StrictWeakOrderingConcept`.
* `SinglePassRange1`'s value type is convertible to both `BinaryPredicate`'s argument types.
* `range_value<SinglePassRange1>::type` is convertible to a type in `OutputIterator`'s set of value types.

[heading Precondition:]

[heading For the non-predicate version:]

* The elements of `rng1` are in ascending order. That is, for each adjacent element pair `[x,y]` of `rng1`, `y < x == false`.
* The elements of `rng2` are in ascending order. That is, for each adjacent element pair `[x,y]` of `rng2`, `y < x == false`.
* The ranges `rng1` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
* The ranges `rng2` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
* `[out, out + distance(rng1) + distance(rng2))` is a valid range.

[heading For the predicate version:]

* The elements of `rng1` are in ascending order. That is, for each adjacent element pair `[x,y]`, of `rng1`, `pred(y, x) == false`.
* The elements of `rng2` are in ascending order. That is, for each adjacent element pair `[x,y]`, of `rng2`, `pred(y, x) == false`.
* The ranges `rng1` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
* The ranges `rng2` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
* `[out, out + distance(rng1) + distance(rng2))` is a valid range.

[heading Complexity]

Linear. There are no comparisons if both `rng1` and `rng2` are empty, otherwise at most `distance(rng1) + distance(rng2) - 1` comparisons.

[endsect]
Commit	Line	Data
7c673cae FG	1	[/
	2	Copyright 2010 Neil Groves
	3	Distributed under the Boost Software License, Version 1.0.
	4	(See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
	5	/]
	6	[section:merge merge]
	7
	8	[heading Prototype]
	9
	10	``
	11	template<
	12	class SinglePassRange1,
	13	class SinglePassRange2,
	14	class OutputIterator
	15	>
	16	OutputIterator merge(const SinglePassRange1& rng1,
	17	const SinglePassRange2& rng2,
	18	OutputIterator out);
	19
	20	template<
	21	class SinglePassRange1,
	22	class SinglePassRange2,
	23	class OutputIterator,
	24	class BinaryPredicate
	25	>
	26	OutputIterator merge(const SinglePassRange1& rng1,
	27	const SinglePassRange2& rng2,
	28	OutputIterator out,
	29	BinaryPredicate pred);
	30	``
	31
	32	[heading Description]
	33
	34	`merge` combines two sorted ranges `rng1` and `rng2` into a single sorted range by copying elements. `merge` is stable. The return value is `out + distance(rng1) + distance(rng2)`.
	35
	36	The two versions of `merge` differ by how they compare the elements.
	37
	38	The non-predicate version uses the `operator<()` for the range value type. The predicate version uses the predicate instead of `operator<()`.
	39
	40	[heading Definition]
	41
	42	Defined in the header file `boost/range/algorithm/merge.hpp`
	43
	44	[heading Requirements]
	45
	46	[*For the non-predicate version:]
	47
	48	* `SinglePassRange1` is a model of the __single_pass_range__ Concept.
	49	* `SinglePassRange2` is a model of the __single_pass_range__ Concept.
	50	* `range_value<SinglePassRange1>::type` is the same as `range_value<SinglePassRange2>::type`.
	51	* `range_value<SinglePassRange1>::type` is a model of the `LessThanComparableConcept`.
	52	* The ordering on objects of `range_value<SinglePassRange1>::type` is a [*/strict weak ordering/], as defined in the `LessThanComparableConcept` requirements.
	53	* `range_value<SinglePassRange1>::type` is convertible to a type in `OutputIterator`'s set of value types.
	54
	55	[*For the predicate version:]
	56
	57	* `SinglePassRange1` is a model of the __single_pass_range__ Concept.
	58	* `SinglePassRange2` is a model of the __single_pass_range__ Concept.
	59	* `range_value<SinglePassRange1>::type` is the same as `range_value<SinglePassRange2>::type`.
	60	* `BinaryPredicate` is a model of the `StrictWeakOrderingConcept`.
	61	* `SinglePassRange1`'s value type is convertible to both `BinaryPredicate`'s argument types.
	62	* `range_value<SinglePassRange1>::type` is convertible to a type in `OutputIterator`'s set of value types.
	63
	64	[heading Precondition:]
65
66	[heading For the non-predicate version:]
67
68	* The elements of `rng1` are in ascending order. That is, for each adjacent element pair `[x,y]` of `rng1`, `y < x == false`.
69	* The elements of `rng2` are in ascending order. That is, for each adjacent element pair `[x,y]` of `rng2`, `y < x == false`.
70	* The ranges `rng1` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
71	* The ranges `rng2` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
72	* `[out, out + distance(rng1) + distance(rng2))` is a valid range.
73
74	[heading For the predicate version:]
75
76	* The elements of `rng1` are in ascending order. That is, for each adjacent element pair `[x,y]`, of `rng1`, `pred(y, x) == false`.
77	* The elements of `rng2` are in ascending order. That is, for each adjacent element pair `[x,y]`, of `rng2`, `pred(y, x) == false`.
78	* The ranges `rng1` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
79	* The ranges `rng2` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
80	* `[out, out + distance(rng1) + distance(rng2))` is a valid range.
81
82	[heading Complexity]
83
84	Linear. There are no comparisons if both `rng1` and `rng2` are empty, otherwise at most `distance(rng1) + distance(rng2) - 1` comparisons.
85
86	[endsect]
87
88