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Making use of the new quickbook import feature.

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[SVN r3621]
This commit is contained in:
Daniel James
2007-01-10 00:07:33 +00:00
parent f979c07d2e
commit 7468336d3a
2 changed files with 83 additions and 32 deletions
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37
doc/hash_equality.qbk
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@@ -30,39 +30,12 @@ Alternatively, you might wish to use a different equality function. If so, make
sure you use a hash function that matches it. For example, a
case-insensitive dictionary:
struct iequal_to
: std::binary_function<std::string, std::string, bool>
{
bool operator()(std::string const& x,
std::string const& y) const
{
return boost::algorithm::iequals(x, y);
}
};
[import src_code/insensitive.cpp]
[case_insensitive_functions]
[case_insensitive_dictionary]
struct ihash
: std::unary_function<std::string, bool>
{
bool operator()(std::string const& x) const
{
std::size_t seed = 0;
for(std::string::const_iterator it = x.begin();
it != x.end(); ++it)
{
boost::hash_combine(seed, std::tolower(*it));
}
return seed;
}
};
struct word_info {
// ...
};
boost::unordered_map<std::string, word_info, iequal_to, ihash>
idictionary;
A more generic version of this example is available at:
[@../../libs/unordered/examples/case_insensitive.hpp /libs/unordered/examples/case_insensitive.hpp]
[h2 Custom Types]

78
doc/src_code/insensitive.cpp Normal file
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@@ -0,0 +1,78 @@
// Copyright 2006 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 <boost/unordered_map.hpp>
#include <boost/detail/lightweight_test.hpp>
#include <boost/algorithm/string/predicate.hpp>
//[case_insensitive_functions
struct iequal_to
: std::binary_function<std::string, std::string, bool>
{
bool operator()(std::string const& x,
std::string const& y) const
{
return boost::algorithm::iequals(x, y);
}
};
struct ihash
: std::unary_function<std::string, bool>
{
bool operator()(std::string const& x) const
{
std::size_t seed = 0;
for(std::string::const_iterator it = x.begin();
it != x.end(); ++it)
{
boost::hash_combine(seed, std::toupper(*it));
}
return seed;
}
};
struct word_info;
//]
struct word_info {
int tag;
explicit word_info(int t = 0) : tag(t) {}
};
int main() {
//[case_insensitive_dictionary
boost::unordered_map<std::string, word_info, ihash, iequal_to>
idictionary;
//]
BOOST_TEST(idictionary.empty());
idictionary["one"] = word_info(1);
BOOST_TEST(idictionary.size() == 1);
BOOST_TEST(idictionary.find("ONE") != idictionary.end() &&
idictionary.find("ONE") == idictionary.find("one"));
idictionary.insert(std::make_pair("ONE", word_info(2)));
BOOST_TEST(idictionary.size() == 1);
BOOST_TEST(idictionary.find("ONE") != idictionary.end() &&
idictionary.find("ONE")->first == "one" &&
idictionary.find("ONE")->second.tag == 1);
idictionary["One"] = word_info(3);
BOOST_TEST(idictionary.size() == 1);
BOOST_TEST(idictionary.find("ONE") != idictionary.end() &&
idictionary.find("ONE")->first == "one" &&
idictionary.find("ONE")->second.tag == 3);
idictionary["two"] = word_info(4);
BOOST_TEST(idictionary.size() == 2);
BOOST_TEST(idictionary.find("two") != idictionary.end() &&
idictionary.find("TWO")->first == "two" &&
idictionary.find("Two")->second.tag == 4);
return boost::report_errors();
}