.. Iterators/Iterator Metafunctions//next |30 .. Copyright Aleksey Gurtovoy, David Abrahams 2007. .. 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) next ==== Synopsis -------- .. parsed-literal:: template typename Iterator > struct next { typedef |unspecified| type; }; Description ----------- Returns the next iterator in the sequence. |Note:| ``next`` has a number of overloaded meanings, depending on the type of its argument. For instance, if ``X`` is an |Integral Constant|, ``next`` returns an incremented |Integral Constant| of the same type. The following specification is iterator-specific. Please refer to the corresponding concept's documentation for the details of the alternative semantics |-- end note|. Header ------ .. parsed-literal:: #include Parameters ---------- +---------------+---------------------------+-----------------------------------+ | Parameter | Requirement | Description | +===============+===========================+===================================+ | ``Iterator`` | |Forward Iterator|. | An iterator to increment. | +---------------+---------------------------+-----------------------------------+ Expression semantics -------------------- For any |Forward Iterator|\ s ``iter``: .. parsed-literal:: typedef next::type j; :Return type: |Forward Iterator|. :Precondition: ``iter`` is incrementable. :Semantics: ``j`` is an iterator pointing to the next element in the sequence, or is past-the-end. If ``iter`` is a user-defined iterator, the library-provided default implementation is equivalent to .. parsed-literal:: typedef iter::next j; Complexity ---------- Amortized constant time. Example ------- .. parsed-literal:: typedef vector_c v; typedef begin::type first; typedef end::type last; BOOST_MPL_ASSERT(( is_same< next::type, last > )); See also -------- |Iterators|, |begin| / |end|, |prior|, |deref|
