Note: This paper was approved on Saturday at the Issaquah WA USA ISO C++ meeting to be turned into a Concepts Technical Specification working draft for expected adoption at our next meeting (June in Rapperswil, Switzerland).
A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.
Document number: N3929
by Andrew Sutton
C++ has long provided language support for generic programming in the form of templates. However, these templates are unconstrained, allowing any type or value to be substituted for a template argument, often resulting in compiler errors. What is lacking is a specification of an interface for a template, separate from its implementation, so that a use of a template can be selected among alternative templates and checked in isolation.