use_default.qbk 933 B

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  1. [/
  2. Copyright 2019 Glen Joseph Fernandes
  3. (glenjofe@gmail.com)
  4. Distributed under the Boost Software License, Version 1.0.
  5. (http://www.boost.org/LICENSE_1_0.txt)
  6. ]
  7. [section:use_default use_default]
  8. [section Overview]
  9. The header <boost/core/use_default.hpp> provides the type `boost::use_default`
  10. which is used by other Boost libraries as a sentinel type in a templates to
  11. indicate defaults.
  12. [endsect]
  13. [section Example]
  14. ```
  15. template<class Derived, class Base,
  16. class Value = boost::use_default,
  17. class CategoryOrTraversal = boost::use_default,
  18. class Reference = boost::use_default,
  19. class Difference = boost::use_default>
  20. class iterator_adaptor;
  21. template<class Value>
  22. class node_iterator
  23. : public iterator_adaptor<node_iterator<Value>, Value*,
  24. boost::use_default, boost::forward_traversal_tag>;
  25. ```
  26. [endsect]
  27. [section Reference]
  28. ```
  29. namespace boost {
  30. struct use_default { };
  31. }
  32. ```
  33. [endsect]
  34. [endsect]