2006-08-22 15:57:13 +00:00
< html >
< head >
< meta http-equiv = "Content-Type" content = "text/html; charset=ISO-8859-1" >
< title > Random
Access Sequence< / title >
< link rel = "stylesheet" href = "../../../boostbook.css" type = "text/css" >
< meta name = "generator" content = "DocBook XSL Stylesheets V1.66.1" >
< link rel = "start" href = "../../../index.html" title = "Chapter<65> 1.<2E> Fusion 2.0" >
< link rel = "up" href = "../concepts.html" title = "Concepts" >
< link rel = "prev" href = "bidirectional_sequence.html" title = "Bidirectional
Sequence">
< link rel = "next" href = "associative_sequence.html" title = "Associative
Sequence">
< / head >
< body bgcolor = "white" text = "black" link = "#0000FF" vlink = "#840084" alink = "#0000FF" >
< table cellpadding = "2" width = "100%" >
< td valign = "top" > < img alt = "Boost C++ Libraries" width = "277" height = "86" src = "../../../../../../../boost.png" > < / td >
< td align = "center" > < a href = "../../../../../../../index.htm" > Home< / a > < / td >
< td align = "center" > < a href = "../../../../../../libraries.htm" > Libraries< / a > < / td >
< td align = "center" > < a href = "../../../../../../../people/people.htm" > People< / a > < / td >
< td align = "center" > < a href = "../../../../../../../more/faq.htm" > FAQ< / a > < / td >
< td align = "center" > < a href = "../../../../../../../more/index.htm" > More< / a > < / td >
< / table >
< hr >
< div class = "spirit-nav" >
< a accesskey = "p" href = "bidirectional_sequence.html" > < img src = "../../../images/prev.png" alt = "Prev" > < / a > < a accesskey = "u" href = "../concepts.html" > < img src = "../../../images/up.png" alt = "Up" > < / a > < a accesskey = "h" href = "../../../index.html" > < img src = "../../../images/home.png" alt = "Home" > < / a > < a accesskey = "n" href = "associative_sequence.html" > < img src = "../../../images/next.png" alt = "Next" > < / a >
< / div >
< div class = "section" lang = "en" >
< div class = "titlepage" > < div > < div > < h4 class = "title" >
< a name = "fusion.sequences.concepts.random_access_sequence" > < / a > < a href = "random_access_sequence.html" title = "Random
Access Sequence">Random
Access Sequence< / a > < / h4 > < / div > < / div > < / div >
< a name = "fusion.sequences.concepts.random_access_sequence.description" > < / a > < h5 >
2006-12-14 08:41:22 +00:00
< a name = "id479908" > < / a >
2006-08-22 15:57:13 +00:00
< a href = "random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.description" > Description< / a >
< / h5 >
< p >
A Random Access Sequence is a < a href = "bidirectional_sequence.html" title = "Bidirectional
Sequence">Bidirectional
Sequence< / a > whose iterators model < a href = "../../iterators/concepts/random_access_iterator.html" title = "Random
Access Iterator">Random
Access Iterator< / a > . It guarantees constant time access to arbitrary
sequence elements.
< / p >
< a name = "fusion.sequences.concepts.random_access_sequence.refinement_of" > < / a > < h5 >
2006-12-14 08:41:22 +00:00
< a name = "id479960" > < / a >
2006-08-22 15:57:13 +00:00
< a href = "random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.refinement_of" > Refinement
of< / a >
< / h5 >
< p >
< a href = "bidirectional_sequence.html" title = "Bidirectional
Sequence">Bidirectional
Sequence< / a >
< / p >
< div class = "variablelist" >
< p class = "title" > < b > Notation< / b > < / p >
< dl >
< dt > < span class = "term" > < tt class = "computeroutput" > < span class = "identifier" > s< / span > < / tt > < / span > < / dt >
< dd >
A Random Access Sequence
< / dd >
< dt > < span class = "term" > < tt class = "computeroutput" > < span class = "identifier" > S< / span > < / tt > < / span > < / dt >
< dd >
A Random Access Sequence type
< / dd >
< dt > < span class = "term" > < tt class = "computeroutput" > < span class = "identifier" > N< / span > < / tt > < / span > < / dt >
< dd >
An integral constant
< / dd >
< dt > < span class = "term" > < tt class = "computeroutput" > < span class = "identifier" > o< / span > < / tt > < / span > < / dt >
< dd >
An arbitrary object
< / dd >
< dt > < span class = "term" > < tt class = "computeroutput" > < span class = "identifier" > e< / span > < / tt > < / span > < / dt >
< dd >
A Sequence element
< / dd >
< / dl >
< / div >
< a name = "fusion.sequences.concepts.random_access_sequence.valid_expressions" > < / a > < h5 >
2006-12-14 08:41:22 +00:00
< a name = "id480096" > < / a >
2006-08-22 15:57:13 +00:00
< a href = "random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.valid_expressions" > Valid
Expressions< / a >
< / h5 >
< p >
In addition to the requirements defined in < a href = "bidirectional_sequence.html" title = "Bidirectional
Sequence">Bidirectional
Sequence< / a > , for any Random Access Sequence the following must be met:
< / p >
2006-10-30 01:20:23 +00:00
< div class = "informaltable" > < table class = "table" >
2006-08-22 15:57:13 +00:00
< colgroup >
< col >
< col >
< col >
< col >
< / colgroup >
< thead > < tr >
< th > Expression< / th >
< th > Return type< / th >
< th > Type Requirements< / th >
< th > Runtime
Complexity< / th >
< / tr > < / thead >
< tbody >
< tr >
< td > < tt class = "computeroutput" > < a href = "../intrinsics/functions/begin.html" title = "begin" > < tt class = "computeroutput" > < span class = "identifier" > begin< / span > < / tt > < / a > < span class = "special" > (< / span > < span class = "identifier" > s< / span > < span class = "special" > )< / span > < / tt > < / td >
< td > < a href = "../../iterators/concepts/random_access_iterator.html" title = "Random
Access Iterator">Random
Access Iterator< / a > < / td >
< td > <EFBFBD> < / td >
< td > Constant< / td >
< / tr >
< tr >
< td > < tt class = "computeroutput" > < a href = "../intrinsics/functions/end.html" title = "end" > < tt class = "computeroutput" > < span class = "identifier" > end< / span > < / tt > < / a > < span class = "special" > (< / span > < span class = "identifier" > s< / span > < span class = "special" > )< / span > < / tt > < / td >
< td > < a href = "../../iterators/concepts/random_access_iterator.html" title = "Random
Access Iterator">Random
Access Iterator< / a > < / td >
< td > <EFBFBD> < / td >
< td > Constant< / td >
< / tr >
< tr >
< td > < tt class = "computeroutput" > < a href = "../intrinsics/functions/at.html" title = "at" > < tt class = "computeroutput" > < span class = "identifier" > at< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > N< / span > < span class = "special" > > (< / span > < span class = "identifier" > s< / span > < span class = "special" > )< / span > < / tt > < / td >
< td > Any
type< / td >
< td > <EFBFBD> < / td >
< td > Constant< / td >
< / tr >
< tr >
< td > < tt class = "computeroutput" > < a href = "../intrinsics/functions/at.html" title = "at" > < tt class = "computeroutput" > < span class = "identifier" > at< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > N< / span > < span class = "special" > > (< / span > < span class = "identifier" > s< / span > < span class = "special" > )< / span > <EFBFBD> < span class = "special" > =< / span > <EFBFBD> < span class = "identifier" > o< / span > < / tt > < / td >
< td > Any
type< / td >
< td >
< tt class = "computeroutput" > < span class = "identifier" > s< / span > < / tt >
is mutable and < tt class = "computeroutput" > < span class = "identifier" > e< / span > <EFBFBD> < span class = "special" > =< / span > <EFBFBD> < span class = "identifier" > o< / span > < / tt > ,
where < tt class = "computeroutput" > < span class = "identifier" > e< / span > < / tt > is the first
element in the sequence, is a valid expression.< / td >
< td > Constant< / td >
< / tr >
< / tbody >
2006-10-30 01:20:23 +00:00
< / table > < / div >
2006-08-22 15:57:13 +00:00
< a name = "fusion.sequences.concepts.random_access_sequence.result_type_expressions" > < / a > < h5 >
2006-12-14 08:41:22 +00:00
< a name = "id480454" > < / a >
2006-08-22 15:57:13 +00:00
< a href = "random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.result_type_expressions" > Result
Type Expressions< / a >
< / h5 >
2006-10-30 01:20:23 +00:00
< div class = "informaltable" > < table class = "table" >
2006-08-22 15:57:13 +00:00
< colgroup >
< col >
< col >
< / colgroup >
< thead > < tr >
< th > Expression< / th >
< th > Compile Time Complexity< / th >
< / tr > < / thead >
< tbody >
< tr >
< td > < tt class = "computeroutput" > < a href = "../intrinsics/metafunctions/begin.html" title = "begin" > < tt class = "computeroutput" > < span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > begin< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > S< / span > < span class = "special" > > ::< / span > < span class = "identifier" > type< / span > < / tt > < / td >
< td > Amortized constant
time< / td >
< / tr >
< tr >
< td > < tt class = "computeroutput" > < a href = "../intrinsics/metafunctions/end.html" title = "end" > < tt class = "computeroutput" > < span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > end< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > S< / span > < span class = "special" > > ::< / span > < span class = "identifier" > type< / span > < / tt > < / td >
< td > Amortized constant
time< / td >
< / tr >
< tr >
< td > < tt class = "computeroutput" > < a href = "../intrinsics/metafunctions/at.html" title = "at" > < tt class = "computeroutput" > < span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > at< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > S< / span > < span class = "special" > ,< / span > <EFBFBD> < span class = "identifier" > N< / span > < span class = "special" > > ::< / span > < span class = "identifier" > type< / span > < / tt > < / td >
< td > Amortized constant
time< / td >
< / tr >
< tr >
< td > < tt class = "computeroutput" > < a href = "../intrinsics/metafunctions/value_at.html" title = "value_at" > < tt class = "computeroutput" > < span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > value_at< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > S< / span > < span class = "special" > ,< / span > <EFBFBD> < span class = "identifier" > N< / span > < span class = "special" > > ::< / span > < span class = "identifier" > type< / span > < / tt > < / td >
< td > Amortized constant
time< / td >
< / tr >
< / tbody >
2006-10-30 01:20:23 +00:00
< / table > < / div >
2006-08-22 15:57:13 +00:00
< p class = "blurb" >
< span class = "inlinemediaobject" > < img src = "../../../images/note.png" alt = "note" > < / span > <EFBFBD> < tt class = "computeroutput" > < a href = "../intrinsics/metafunctions/at.html" title = "at" > < tt class = "computeroutput" > < span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > at< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > S< / span > < span class = "special" > ,< / span > <EFBFBD> < span class = "identifier" > N< / span > < span class = "special" > > < / span > < / tt >
returns the actual type returned by < tt class = "computeroutput" > < a href = "../intrinsics/functions/at.html" title = "at" > < tt class = "computeroutput" > < span class = "identifier" > at< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > N< / span > < span class = "special" > > (< / span > < span class = "identifier" > s< / span > < span class = "special" > )< / span > < / tt > . In
most cases, this is a reference. Hence, there is no way to know the exact
element type using < tt class = "computeroutput" > < a href = "../intrinsics/metafunctions/at.html" title = "at" > < tt class = "computeroutput" > < span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > at< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > S< / span > < span class = "special" > ,< / span > <EFBFBD> < span class = "identifier" > N< / span > < span class = "special" > > < / span > < / tt > .The
element at < tt class = "computeroutput" > < span class = "identifier" > N< / span > < / tt > may actually
be a reference to begin with. For this purpose, you can use < tt class = "computeroutput" > < a href = "../intrinsics/metafunctions/value_at.html" title = "value_at" > < tt class = "computeroutput" > < span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > value_at< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > S< / span > < span class = "special" > ,< / span > <EFBFBD> < span class = "identifier" > N< / span > < span class = "special" > > < / span > < / tt > .
< / p >
< a name = "fusion.sequences.concepts.random_access_sequence.expression_semantics" > < / a > < h5 >
2006-12-14 08:41:22 +00:00
< a name = "id481022" > < / a >
2006-08-22 15:57:13 +00:00
< a href = "random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.expression_semantics" > Expression
Semantics< / a >
< / h5 >
< p >
The semantics of an expression are defined only where they differ from,
or are not defined in < a href = "bidirectional_sequence.html" title = "Bidirectional
Sequence">Bidirectional
Sequence< / a > .
< / p >
2006-10-30 01:20:23 +00:00
< div class = "informaltable" > < table class = "table" >
2006-08-22 15:57:13 +00:00
< colgroup >
< col >
< col >
< / colgroup >
< thead > < tr >
< th > Expression< / th >
< th > Semantics< / th >
< / tr > < / thead >
< tbody > < tr >
< td > < tt class = "computeroutput" > < a href = "../intrinsics/functions/at.html" title = "at" > < tt class = "computeroutput" > < span class = "identifier" > at< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > N< / span > < span class = "special" > > (< / span > < span class = "identifier" > s< / span > < span class = "special" > )< / span > < / tt > < / td >
< td > The
Nth element from the beginning of the sequence; see < a href = "../intrinsics/functions/at.html" title = "at" > < tt class = "computeroutput" > < span class = "identifier" > at< / span > < / tt > < / a > .< / td >
< / tr > < / tbody >
2006-10-30 01:20:23 +00:00
< / table > < / div >
2006-08-22 15:57:13 +00:00
< a name = "fusion.sequences.concepts.random_access_sequence.models" > < / a > < h5 >
2006-12-14 08:41:22 +00:00
< a name = "id481161" > < / a >
2006-08-22 15:57:13 +00:00
< a href = "random_access_sequence.html#fusion.sequences.concepts.random_access_sequence.models" > Models< / a >
< / h5 >
< div class = "itemizedlist" > < ul type = "disc" >
< li > < a href = "../adapted/std__pair.html" title = "std::pair" > < tt class = "computeroutput" > < span class = "identifier" > std< / span > < span class = "special" > ::< / span > < span class = "identifier" > pair< / span > < / tt > < / a > < / li >
< li > < a href = "../adapted/boost__array.html" title = "boost::array" > < tt class = "computeroutput" > < span class = "identifier" > boost< / span > < span class = "special" > ::< / span > < span class = "identifier" > array< / span > < / tt > < / a > < / li >
< li > < a href = "../containers/vector.html" title = "vector" > < tt class = "computeroutput" > < span class = "identifier" > vector< / span > < / tt > < / a > < / li >
< li >
< a href = "../views/iterator_range.html" title = "iterator_range" > < tt class = "computeroutput" > < span class = "identifier" > iterator_range< / span > < / tt > < / a >
(where adapted sequence is a Random Access Sequence)
< / li >
< li >
< a href = "../views/transform_view.html" title = "transform_view" > < tt class = "computeroutput" > < span class = "identifier" > transform_view< / span > < / tt > < / a >
(where adapted sequence is a Random Access Sequence)
< / li >
< li > < a href = "../views/reverse_view.html" title = "reverse_view" > < tt class = "computeroutput" > < span class = "identifier" > reverse_view< / span > < / tt > < / a > < / li >
< / ul > < / div >
< / div >
< table xmlns:rev = "http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width = "100%" > < tr >
< td align = "left" > < / td >
< td align = "right" > < small > Copyright <20> 2001-2005 Joel de Guzman, Dan Marsden< / small > < / td >
< / tr > < / table >
< hr >
< div class = "spirit-nav" >
< a accesskey = "p" href = "bidirectional_sequence.html" > < img src = "../../../images/prev.png" alt = "Prev" > < / a > < a accesskey = "u" href = "../concepts.html" > < img src = "../../../images/up.png" alt = "Up" > < / a > < a accesskey = "h" href = "../../../index.html" > < img src = "../../../images/home.png" alt = "Home" > < / a > < a accesskey = "n" href = "associative_sequence.html" > < img src = "../../../images/next.png" alt = "Next" > < / a >
< / div >
< / body >
< / html >
