DOKK / manpages / debian 11 / libbobcat-dev / hash.3bobcat.en
FBB::Hash(3bobcat) Key hashing containers FBB::Hash(3bobcat)

FBB::Hash - Various mapping template classes using hashing

#include <bobcat/hash>

The FBB:Hash group of template classes offer hashing-based mapping. Various variants are available, all based on the facilities offered by the unordered_map.

The hash-map offered in the unordered_map container has a fairly complex construction interface, and Hash is an attempt to simplify this part of its interface. In practice, hashing uses a textual key, which may be std::string or char * based, and the keys may be used either case sensitively or case insensitively. Hash merely requires its users to specify the map’s value type, while the key may be a char const * or std::string, used case sensitively or case insensitively.

FBB
All constructors, members, operators and manipulators, mentioned in this man-page, are defined in the namespace FBB.

std::unordered_map, using various instantiations.

All variants define value_type as the corresponding unordered_map value_type. In practice a value_type defines a std::pair<Key, Value>, where Key represents the hash’s key-type and Value represents the hash’s value type.

Variants of the FBB::Hash container are available for char const * or std::string keys, used case sensitively or case insensitively.

All variants support default and move construction (as well as move assignment), support construction from initializer lists. and support construction from iterators defining a half-open range of value_type values.

The following variants are available (showing their default constructors). Value refers to the value type stored in the hash table.

HashCharPtr<Value>():
this hash table uses case sensitive char const * keys;
HashCharCasePtr<Value>():
this hash table uses case insensitive char const * keys;
HashString<Value>():
this hash table uses case sensitive std::string keys;
HashStringCase<Value>():
this hash table uses case insensitive std::string keys;

In addition to the index operator inherited from unordered_map the overloaded copy and move assignment operators are available for all Hash containers.

All members of the unordered_map container are available, as Hash inherits from this template class.


#include <iostream>
#include <bobcat/hash>

using namespace std;
using namespace FBB;

pair<char const *, size_t> ap[] =
{
pair<char const *, size_t>("one", 1),
pair<char const *, size_t>("two", 2),
};

int main()
{
HashCharPtr<size_t> hcp;
HashCharPtr<size_t> hcp2(ap, ap + 2);
HashCharPtr<size_t> hcp3(hcp2);
hcp = hcp2;

cout << hcp2["one"] << endl;
}

bobcat/hash - defines the class interface

bobcat(7)

None Reported.

https://fbb-git.gitlab.io/bobcat/: gitlab project page;
bobcat_5.07.00-x.dsc: detached signature;
bobcat_5.07.00-x.tar.gz: source archive;
bobcat_5.07.00-x_i386.changes: change log;
libbobcat1_5.07.00-x_*.deb: debian package containing the libraries;
libbobcat1-dev_5.07.00-x_*.deb: debian package containing the libraries, headers and manual pages;

Bobcat is an acronym of `Brokken’s Own Base Classes And Templates’.

This is free software, distributed under the terms of the GNU General Public License (GPL).

Frank B. Brokken (f.b.brokken@rug.nl).

2005-2020 libbobcat-dev_5.07.00