Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

This is an old version of boost. Click here for the latest version's documentation home page.
PrevUpHomeNext

Function hash_range

boost::hash_range — Calculate the combined hash value of the elements of an iterator range.

Synopsis

template<typename It> std::size_t hash_range(It first, It last);
template<typename It> void hash_range(std::size_t& seed, It first, It last);

Description

Effects:

For the two argument overload:

size_t seed = 0;

for(; first != last; ++first)
{
    hash_combine(seed, *first);
}

return seed;

For the three arguments overload:
for(; first != last; ++first)
{
    hash_combine(seed, *first);
}

Notes:

hash_range is sensitive to the order of the elements so it wouldn't be appropriate to use this with an unordered container.

This is an extension to TR1

Throws:

Only throws if hash_value(std::iterator_traits<It>::value_type) throws. hash_range(std::size_t&, It, It) has basic exception safety as long as hash_value(std::iterator_traits<It>::value_type) has basic exception safety.

Copyright 2005, 2006 Daniel James

PrevUpHomeNext