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Document number: N3909

Date: 2014-02-10

A SFINAE-Friendly std::iterator_traits, v2

by Walter Brown

Excerpt:

This paper proposes to reformulate the specification of iterator_traits so as to avoid a hard error when its template argument does not have the member types and other characteristics expected of a non-pointer iterator, and thus to make the trait conveniently usable in a SFINAE context.

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6 Acknowledgments

Many thanks to the readers of early drafts of this paper for their thoughtful comments. Special thanks to Howard Hinnant for his suggestion to validate the nested iterator_category.