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Section: 26.6.9[alg.find.first.of]Status:CD1Submitter: Doug GregorOpened: 2006-04-25Last modified: 2016-01-28
Priority:Not Prioritized
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Discussion:
In 25.1.4 Find First [lib.alg.find.first], the two iterator type parameters tofind_first_of are specified to require Forward Iterators, as follows:
template<class ForwardIterator1, class ForwardIterator2> ForwardIterator1 find_first_of(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2, ForwardIterator2 last2);template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>ForwardIterator1 find_first_of(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);
However, ForwardIterator1 need not actually be a Forward Iterator; an InputIterator suffices, because we do not need the multi-pass property of the ForwardIterator or a true reference.
Proposed resolution:
Change the declarations offind_first_of to:
template<classForwardIterator1InputIterator1, class ForwardIterator2>ForwardIterator1InputIterator1 find_first_of(ForwardIterator1InputIterator1 first1,ForwardIterator1InputIterator1 last1, ForwardIterator2 first2, ForwardIterator2 last2);template<classForwardIterator1InputIterator1, class ForwardIterator2, class BinaryPredicate>ForwardIterator1InputIterator1 find_first_of(ForwardIterator1InputIterator1 first1,ForwardIterator1InputIterator1 last1, ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred);