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Diffstat (limited to 'src/boost/libs/container_hash/examples/books.cpp')
-rw-r--r-- | src/boost/libs/container_hash/examples/books.cpp | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/src/boost/libs/container_hash/examples/books.cpp b/src/boost/libs/container_hash/examples/books.cpp new file mode 100644 index 00000000..3dfa547e --- /dev/null +++ b/src/boost/libs/container_hash/examples/books.cpp @@ -0,0 +1,51 @@ + +// Copyright 2005-2009 Daniel James. +// 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) + +#include "./books.hpp" +#include <boost/container_hash/hash.hpp> +#include <cassert> + +// If std::unordered_set was available: +//#include <unordered_set> + +// This example illustrates how to use boost::hash with a custom hash function. +// For full details, see the tutorial. + +int main() +{ + library::book knife(3458, "Zane Grey", "The Hash Knife Outfit"); + library::book dandelion(1354, "Paul J. Shanley", "Hash & Dandelion Greens"); + + boost::hash<library::book> book_hasher; + std::size_t knife_hash_value = book_hasher(knife); + (void)knife_hash_value; // suppress unused variable warning + + // If std::unordered_set was available: + // + //std::unordered_set<library::book, boost::hash<library::book> > books; + //books.insert(knife); + //books.insert(library::book(2443, "Lindgren, Torgny", "Hash")); + //books.insert(library::book(1953, "Snyder, Bernadette M.", + // "Heavenly Hash: A Tasty Mix of a Mother's Meditations")); + + //assert(books.find(knife) != books.end()); + //assert(books.find(dandelion) == books.end()); + + return 0; +} + +namespace library +{ + bool operator==(book const& a, book const& b) + { + return a.id == b.id; + } + + std::size_t hash_value(book const& b) + { + boost::hash<int> hasher; + return hasher(b.id); + } +} |