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Returns the result type of at_c[8].
template< typename Seq, int N> struct at_c { typedef unspecified type; };
Table 1.29. Parameters
|
Parameter |
Requirement |
Description |
|---|---|---|
|
|
A model of Random Access Sequence |
Argument sequence |
|
|
Positive integer index |
Index of element |
result_of::at_c<Seq, N>::type
Return type: Any type
Precondition: 0
<= N
< (where result_of::size<Seq>::valueSeq
is not Unbounded
Sequence)
Semantics: Returns the result type of
using at_c to access the Nth element of Seq.
#include <boost/fusion/sequence/intrinsic/at.hpp> #include <boost/fusion/include/at.hpp>
typedefvector<int,float,char> vec; BOOST_MPL_ASSERT((boost::is_same<result_of::at_c<vec, 1>::type, float&>));
[8]
result_of::at_c reflects the actual return
type of the function at_c. Sequence(s)
typically return references to its elements via the at_c function. If you want
to get the actual element type, use result_of::value_at_c