wxWidgets/interface/wx/hashmap.h
Vadim Zeitlin ccba6d73f9 Fix use of Doxygen grouping
Fix wrong use of Doxygen grouping-related markup which somehow worked in
older Doxygen versions, but doesn't work any longer.

This fixes the problem with the "Functions by Category" pages being
empty in the resulting HTML documentation and wrong documentation being
shown for a bunch of wxString members.

This is a combined cherry-pick of the following master commits:

bd92523bc5 Fix use of Doxygen @addtogroup command
4c46e01b14 Remove stray Doxygen end group marker
8ac10d28f8 Fix all the other comments with Doxygen grouping commands too
c0f1ecf263 Fix another unbalanced Doxygen grouping command after last commit

See #22248, #22572.
2022-08-18 19:15:47 +02:00

262 lines
8.3 KiB
Objective-C

/////////////////////////////////////////////////////////////////////////////
// Name: hashmap.h
// Purpose: interface of wxHashMap
// Author: wxWidgets team
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
/**
@class wxHashMap
This is a simple, type-safe, and reasonably efficient hash map class,
whose interface is a subset of the interface of STL containers.
In particular, the interface is modelled after std::map, and the various,
non-standard, std::hash_map (http://www.cppreference.com/wiki/stl/map/start).
Example:
@code
class MyClass { ... };
// declare a hash map with string keys and int values
WX_DECLARE_STRING_HASH_MAP( int, MyHash5 );
// same, with int keys and MyClass* values
WX_DECLARE_HASH_MAP( int, MyClass*, wxIntegerHash, wxIntegerEqual, MyHash1 );
// same, with wxString keys and int values
WX_DECLARE_STRING_HASH_MAP( int, MyHash3 );
// same, with wxString keys and values
WX_DECLARE_STRING_HASH_MAP( wxString, MyHash2 );
MyHash1 h1;
MyHash2 h2;
// store and retrieve values
h1[1] = new MyClass( 1 );
h1[10000000] = NULL;
h1[50000] = new MyClass( 2 );
h2["Bill"] = "ABC";
wxString tmp = h2["Bill"];
// since element with key "Joe" is not present, this will return
// the default value, which is an empty string in the case of wxString
MyClass tmp2 = h2["Joe"];
// iterate over all the elements in the class
MyHash2::iterator it;
for( it = h2.begin(); it != h2.end(); ++it )
{
wxString key = it->first, value = it->second;
// do something useful with key and value
}
@endcode
@section hashmap_declaringnew Declaring new hash table types
@code
WX_DECLARE_STRING_HASH_MAP( VALUE_T, // type of the values
CLASSNAME ); // name of the class
@endcode
Declares a hash map class named CLASSNAME, with wxString keys and VALUE_T values.
@code
WX_DECLARE_VOIDPTR_HASH_MAP( VALUE_T, // type of the values
CLASSNAME ); // name of the class
@endcode
Declares a hash map class named CLASSNAME, with void* keys and VALUE_T values.
@code
WX_DECLARE_HASH_MAP( KEY_T, // type of the keys
VALUE_T, // type of the values
HASH_T, // hasher
KEY_EQ_T, // key equality predicate
CLASSNAME); // name of the class
@endcode
The HASH_T and KEY_EQ_T are the types used for the hashing function and
key comparison. wxWidgets provides three predefined hashing functions:
@c wxIntegerHash for integer types ( int, long, short, and their unsigned counterparts ),
@c wxStringHash for strings ( wxString, wxChar*, char* ), and @c wxPointerHash for
any kind of pointer.
Similarly three equality predicates: @c wxIntegerEqual, @c wxStringEqual,
@c wxPointerEqual are provided.
Using this you could declare a hash map mapping int values to wxString like this:
@code
WX_DECLARE_HASH_MAP( int,
wxString,
wxIntegerHash,
wxIntegerEqual,
MyHash );
// using a user-defined class for keys
class MyKey { ... };
// hashing function
class MyKeyHash
{
public:
MyKeyHash() { }
unsigned long operator()( const MyKey& k ) const
{
// compute the hash
}
MyKeyHash& operator=(const MyKeyHash&) { return *this; }
};
// comparison operator
class MyKeyEqual
{
public:
MyKeyEqual() { }
bool operator()( const MyKey& a, const MyKey& b ) const
{
// compare for equality
}
MyKeyEqual& operator=(const MyKeyEqual&) { return *this; }
};
WX_DECLARE_HASH_MAP( MyKey, // type of the keys
SOME_TYPE, // any type you like
MyKeyHash, // hasher
MyKeyEqual, // key equality predicate
CLASSNAME); // name of the class
@endcode
@section hashmap_types Types
In the documentation below you should replace wxHashMap with the name you used
in the class declaration.
- wxHashMap::key_type: Type of the hash keys.
- wxHashMap::mapped_type: Type of the values stored in the hash map.
- wxHashMap::value_type: Equivalent to struct { key_type first; mapped_type second }.
- wxHashMap::iterator: Used to enumerate all the elements in a hash map;
it is similar to a value_type*.
- wxHashMap::const_iterator: Used to enumerate all the elements in a constant
hash map; it is similar to a const value_type*.
- wxHashMap::size_type: Used for sizes.
- wxHashMap::Insert_Result: The return value for insert().
@section hashmap_iter Iterators
An iterator is similar to a pointer, and so you can use the usual pointer operations:
++it ( and it++ ) to move to the next element, *it to access the element pointed to,
it->first ( it->second ) to access the key ( value ) of the element pointed to.
Hash maps provide forward only iterators, this means that you can't use \--it,
it + 3, it1 - it2.
@section hashmap_predef Predefined hashmap types
wxWidgets defines the following hashmap types:
- wxLongToLongHashMap (uses long both for keys and values)
- wxStringToStringHashMap (uses wxString both for keys and values)
@library{wxbase}
@category{containers}
*/
class wxHashMap
{
public:
/**
The size parameter is just a hint, the table will resize automatically
to preserve performance.
*/
wxHashMap(size_type size = 10);
/**
Copy constructor.
*/
wxHashMap(const wxHashMap& map);
///@{
/**
Returns an iterator pointing at the first element of the hash map.
Please remember that hash maps do not guarantee ordering.
*/
const_iterator begin() const;
iterator begin();
///@}
/**
Removes all elements from the hash map.
*/
void clear();
/**
Counts the number of elements with the given key present in the map.
This function returns only 0 or 1.
*/
size_type count(const key_type& key) const;
/**
Returns @true if the hash map does not contain any elements, @false otherwise.
*/
bool empty() const;
///@{
/**
Returns an iterator pointing at the one-after-the-last element of the hash map.
Please remember that hash maps do not guarantee ordering.
*/
const_iterator end() const;
iterator end();
///@}
///@{
/**
Erases the element with the given key, and returns the number of elements
erased (either 0 or 1).
*/
size_type erase(const key_type& key);
/**
Erases the element pointed to by the iterator. After the deletion
the iterator is no longer valid and must not be used.
*/
void erase(iterator it);
void erase(const_iterator it);
///@}
///@{
/**
If an element with the given key is present, the functions returns an
iterator pointing at that element, otherwise an invalid iterator is
returned.
@code
hashmap.find( non_existent_key ) == hashmap.end()
@endcode
*/
iterator find(const key_type& key) const;
const_iterator find(const key_type& key) const;
///@}
/**
Inserts the given value in the hash map.
The return value is equivalent to a
@code std::pair<wxHashMap::iterator, bool> @endcode
The iterator points to the inserted element, the boolean value is @true
if @a v was actually inserted.
*/
Insert_Result insert(const value_type& v);
/**
Use the key as an array subscript.
The only difference is that if the given key is not present in the hash map,
an element with the default @c value_type() is inserted in the table.
*/
mapped_type operator[](const key_type& key);
/**
Returns the number of elements in the map.
*/
size_type size() const;
};