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< a name = "fusion.sequence.intrinsic.metafunctions.at_key" > < / a > < a href = "at_key.html" title = "at_key" > at_key< / a > < / h5 > < / div > < / div > < / div >
< a name = "fusion.sequence.intrinsic.metafunctions.at_key.description" > < / a > < h6 >
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< a name = "id513500" > < / a >
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< a href = "at_key.html#fusion.sequence.intrinsic.metafunctions.at_key.description" > Description< / a >
< / h6 >
< p >
Returns the result type of < a href = "../functions/at_key.html" title = "at_key" > < tt class = "computeroutput" > < span class = "identifier" > at_key< / span > < / tt > < / a >
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< sup > [< a name = "id513538" href = "#ftn.id513538" > 7< / a > ]< / sup >
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.
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< a name = "fusion.sequence.intrinsic.metafunctions.at_key.synopsis" > < / a > < h6 >
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< a name = "id513658" > < / a >
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< a href = "at_key.html#fusion.sequence.intrinsic.metafunctions.at_key.synopsis" > Synopsis< / a >
< / h6 >
< pre class = "programlisting" >
< span class = "keyword" > template< / span > < span class = "special" > < < / span >
< span class = "keyword" > typename< / span > < span class = "identifier" > Seq< / span > < span class = "special" > ,< / span >
< span class = "keyword" > typename< / span > < span class = "identifier" > Key< / span > < span class = "special" > > < / span >
< span class = "keyword" > struct< / span > < span class = "identifier" > at_key< / span >
< span class = "special" > {< / span >
< span class = "keyword" > typedef< / span > < span class = "emphasis" > < em > unspecified< / em > < / span > < span class = "identifier" > type< / span > < span class = "special" > ;< / span >
< span class = "special" > };< / span >
< / pre >
< div class = "table" >
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< a name = "id513775" > < / a > < p class = "title" > < b > Table<EFBFBD> 1.30.<2E> Parameters< / b > < / p >
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< table class = "table" summary = "Parameters" >
< colgroup >
< col >
< col >
< col >
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< thead > < tr >
< th >
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Parameter
< / p >
< / th >
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< p >
Requirement
< / p >
< / th >
< th >
< p >
Description
< / p >
< / th >
< / tr > < / thead >
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< tr >
< td >
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< tt class = "computeroutput" > < span class = "identifier" > Seq< / span > < / tt >
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< / td >
< td >
< p >
A model of < a href = "../../concepts/forward_sequence.html" title = "Forward
Sequence">Forward
Sequence< / a >
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Argument sequence
< / p >
< / td >
< / tr >
< tr >
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< tt class = "computeroutput" > < span class = "identifier" > Key< / span > < / tt >
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Any type
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< td >
< p >
Key type
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< a name = "fusion.sequence.intrinsic.metafunctions.at_key.expression_semantics" > < / a > < h6 >
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< a name = "id513914" > < / a >
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< a href = "at_key.html#fusion.sequence.intrinsic.metafunctions.at_key.expression_semantics" > Expression
Semantics< / a >
< / h6 >
< pre class = "programlisting" >
< span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > at_key< / span > < span class = "special" > < < / span > < span class = "identifier" > Seq< / span > < span class = "special" > ,< / span > < span class = "identifier" > Key< / span > < span class = "special" > > ::< / span > < span class = "identifier" > type< / span >
< / pre >
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< span class = "bold" > < b > Return type< / b > < / span > : Any type.
< / p >
< p >
< span class = "bold" > < b > Semantics< / b > < / span > : Returns the result of using
< a href = "../functions/at_key.html" title = "at_key" > < tt class = "computeroutput" > < span class = "identifier" > at_key< / span > < / tt > < / a > to access the element
with key type < tt class = "computeroutput" > < span class = "identifier" > Key< / span > < / tt > in
< tt class = "computeroutput" > < span class = "identifier" > Seq< / span > < / tt > .
< / p >
< p >
/sequence/intrinsic/at_key.hpp>
< / p >
< a name = "fusion.sequence.intrinsic.metafunctions.at_key.example" > < / a > < h6 >
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< a name = "id514066" > < / a >
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< a href = "at_key.html#fusion.sequence.intrinsic.metafunctions.at_key.example" > Example< / a >
< / h6 >
< pre class = "programlisting" >
< span class = "keyword" > typedef< / span > < a href = "../../../container/map.html" title = "map" > < tt class = "computeroutput" > < span class = "identifier" > map< / span > < / tt > < / a > < span class = "special" > < < / span > < a href = "../../../support/pair.html" title = "pair" > < tt class = "computeroutput" > < span class = "identifier" > pair< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "keyword" > int< / span > < span class = "special" > ,< / span > < span class = "keyword" > char< / span > < span class = "special" > > ,< / span > < a href = "../../../support/pair.html" title = "pair" > < tt class = "computeroutput" > < span class = "identifier" > pair< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "keyword" > char< / span > < span class = "special" > ,< / span > < span class = "keyword" > char< / span > < span class = "special" > > ,< / span > < a href = "../../../support/pair.html" title = "pair" > < tt class = "computeroutput" > < span class = "identifier" > pair< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "keyword" > double< / span > < span class = "special" > ,< / span > < span class = "keyword" > char< / span > < span class = "special" > > < / span > < span class = "special" > > < / span > < span class = "identifier" > mymap< / span > < span class = "special" > ;< / span >
< span class = "identifier" > BOOST_MPL_ASSERT< / span > < span class = "special" > ((< / span > < span class = "identifier" > boost< / span > < span class = "special" > ::< / span > < span class = "identifier" > is_same< / span > < span class = "special" > < < / span > < a href = "at_key.html" title = "at_key" > < tt class = "computeroutput" > < span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > at_key< / span > < / tt > < / a > < span class = "special" > < < / span > < span class = "identifier" > mymap< / span > < span class = "special" > ,< / span > < span class = "keyword" > int< / span > < span class = "special" > > ::< / span > < span class = "identifier" > type< / span > < span class = "special" > ,< / span > < span class = "keyword" > char< / span > < span class = "special" > & > ));< / span >
< / pre >
< div class = "footnotes" >
< br > < hr width = "100" align = "left" >
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< div class = "footnote" > < p > < sup > [< a name = "ftn.id513538" href = "#id513538" > 7< / a > ] < / sup >
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< a href = "at_key.html" title = "at_key" > < tt class = "computeroutput" > < span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > at_key< / span > < / tt > < / a > reflects the actual
return type of the function < a href = "../functions/at_key.html" title = "at_key" > < tt class = "computeroutput" > < span class = "identifier" > at_key< / span > < / tt > < / a > . < span class = "underline" > _sequence< / span > _s
typically return references to its elements via the < a href = "../functions/at_key.html" title = "at_key" > < tt class = "computeroutput" > < span class = "identifier" > at_key< / span > < / tt > < / a > function. If you
want to get the actual element type, use < a href = "value_at_key.html" title = "value_at_key" > < tt class = "computeroutput" > < span class = "identifier" > result_of< / span > < span class = "special" > ::< / span > < span class = "identifier" > value_at_key< / span > < / tt > < / a >
< / p > < / div >
< / div >
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< td align = "right" > < div class = "copyright-footer" > < small > Copyright <20> 2001-2007 Joel de Guzman, Dan Marsden, Tobias
Schwinger< p >
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at < a href = "http://www.boost.org/LICENSE_1_0.txt" target = "_top" > http://www.boost.org/LICENSE_1_0.txt< / a > )
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