Unordered associative container wrapping std::unordered_map. More...

#include <hashmap.h>

Public Types
using	Ptr = SharedPtr< HashMap >
	Shared pointer type for HashMap.

using	Data = std::unordered_map< K, V >
	Underlying std::unordered_map storage type.

using	Key = K
	Key type.

using	Value = V
	Value type.

using	Iterator = typename Data::iterator
	Mutable forward iterator.

using	ConstIterator = typename Data::const_iterator
	Const forward iterator.

Public Member Functions
	HashMap ()=default
	Default constructor. Creates an empty hash map.

	HashMap (const HashMap &other)
	Copy constructor.

	HashMap (HashMap &&other) noexcept
	Move constructor.

	HashMap (std::initializer_list< std::pair< const K, V > > initList)
	Constructs a hash map from an initializer list of key-value pairs.

	~HashMap ()=default
	Destructor.

HashMap &	operator= (const HashMap &other)
	Copy assignment operator.

HashMap &	operator= (HashMap &&other) noexcept
	Move assignment operator.

Iterator	begin () noexcept
	Returns a mutable iterator to the first entry.

ConstIterator	begin () const noexcept
	Returns a const iterator to the first entry.

ConstIterator	cbegin () const noexcept
	Returns a const iterator to the first entry.

ConstIterator	constBegin () const noexcept
	Returns a const iterator to the first entry.

Iterator	end () noexcept
	Returns a mutable iterator to one past the last entry.

ConstIterator	end () const noexcept
	Returns a const iterator to one past the last entry.

ConstIterator	cend () const noexcept
	Returns a const iterator to one past the last entry.

ConstIterator	constEnd () const noexcept
	Returns a const iterator to one past the last entry.

bool	isEmpty () const noexcept
	Returns true if the hash map has no entries.

size_t	size () const noexcept
	Returns the number of key-value pairs.

V &	operator[] (const K &key)
	Returns a reference to the value for `key`, inserting a default-constructed value if it does not exist.

const V &	operator[] (const K &key) const
	Returns a const reference to the value for `key`.

V	value (const K &key, const V &defaultValue=V{}) const
	Returns the value for `key`, or `defaultValue` if the key is not present.

bool	contains (const K &key) const
	Returns true if `key` exists in the hash map.

Iterator	find (const K &key)
	Finds the entry for `key`.

ConstIterator	find (const K &key) const
	Const overload of find().

void	insert (const K &key, const V &val)
	Inserts or assigns a key-value pair.

void	insert (const K &key, V &&val)
	Inserts or assigns a key-value pair (move overload).

bool	remove (const K &key)
	Removes the entry for `key`.

Iterator	remove (Iterator pos)
	Removes the entry at `pos`.

void	clear () noexcept
	Removes all entries.

void	swap (HashMap &other) noexcept
	Swaps contents with another hash map.

List< K >	keys () const
	Returns a list of all keys.

List< V >	values () const
	Returns a list of all values.

template<typename Func >
void	forEach (Func &&func) const
	Calls `func` for every key-value pair.

Friends
bool	operator== (const HashMap &lhs, const HashMap &rhs)
	Returns true if both hash maps have identical contents.

bool	operator!= (const HashMap &lhs, const HashMap &rhs)
	Returns true if the hash maps differ.

Detailed Description

template<typename K, typename V>
class HashMap< K, V >

Unordered associative container wrapping std::unordered_map.

Provides a Qt-inspired API over std::unordered_map with consistent naming

Example
HashMap<String, int> cache;

cache.insert("width", 1920);

cache.insert("height", 1080);

int w = cache.value("width", 0); // 1920

List
Dynamic array container wrapping std::vector.
Definition list.h:40

List::insert
Iterator insert(ConstIterator pos, const T &value)
Inserts a value before the position given by an iterator.
Definition list.h:341

conventions matching the rest of libpromeki.

Template Parameters

K Key type (must be hashable).

V Value type.

Constructor & Destructor Documentation

◆ HashMap()

template<typename K , typename V >

HashMap< K, V >::HashMap ( std::initializer_list< std::pair< const K, V > > initList )

inline

Constructs a hash map from an initializer list of key-value pairs.

Parameters

initList Brace-enclosed list of {key, value} pairs.

Member Function Documentation

◆ constBegin()

template<typename K , typename V >

ConstIterator HashMap< K, V >::constBegin ( ) const

inlinenoexcept

Returns a const iterator to the first entry.

◆ constEnd()

template<typename K , typename V >

ConstIterator HashMap< K, V >::constEnd ( ) const

inlinenoexcept

Returns a const iterator to one past the last entry.

◆ find()

template<typename K , typename V >

Iterator HashMap< K, V >::find ( const K & key )

inline

Finds the entry for key.

Parameters

key	The key to search for.

Returns: Iterator to the entry, or end() if not found.

◆ forEach()

template<typename K , typename V >

template<typename Func >

void HashMap< K, V >::forEach ( Func && func ) const

inline

Calls func for every key-value pair.

Template Parameters

Func	Callable with signature void(const K &, const V &).

Parameters

func	The function to invoke.

◆ insert() [1/2]

template<typename K , typename V >

void HashMap< K, V >::insert	(	const K &	key,
		const V &	val
	)

inline

Inserts or assigns a key-value pair.

Parameters

key	The key.
val	The value.

◆ insert() [2/2]

template<typename K , typename V >

void HashMap< K, V >::insert	(	const K &	key,
		V &&	val
	)

inline

Inserts or assigns a key-value pair (move overload).

Parameters

key	The key.
val	The value (moved).

◆ operator[]() [1/2]

template<typename K , typename V >

V & HashMap< K, V >::operator[] ( const K & key )

inline

Returns a reference to the value for key, inserting a default-constructed value if it does not exist.

Parameters

key	The key to look up.

Returns: Reference to the mapped value.

◆ operator[]() [2/2]

template<typename K , typename V >

const V & HashMap< K, V >::operator[] ( const K & key ) const

inline

Returns a const reference to the value for key.

The key must already exist; behavior is undefined otherwise. Prefer value() or find() when the key may not exist.

Parameters

key	The key to look up.

Returns: Const reference to the mapped value.

◆ remove() [1/2]

template<typename K , typename V >

bool HashMap< K, V >::remove ( const K & key )

inline

Removes the entry for key.

Parameters

key	The key to remove.

Returns: True if an entry was removed, false if the key was not found.

◆ remove() [2/2]

template<typename K , typename V >

Iterator HashMap< K, V >::remove ( Iterator pos )

inline

Removes the entry at pos.

Parameters

pos	Iterator to the entry to remove.

Returns: Iterator to the next entry.

◆ swap()

template<typename K , typename V >

void HashMap< K, V >::swap ( HashMap< K, V > & other )

inlinenoexcept

Swaps contents with another hash map.

Parameters

other The hash map to swap with.

◆ value()

template<typename K , typename V >

V HashMap< K, V >::value	(	const K &	key,
		const V &	defaultValue = `V{}`
	)		const

inline

Returns the value for key, or defaultValue if the key is not present.

Parameters

key	The key to look up.
defaultValue	Fallback value.

Returns: The mapped value or the default.

The documentation for this class was generated from the following file:

include/promeki/core/hashmap.h

Public Types

Public Member Functions

Friends

Detailed Description

Constructor & Destructor Documentation

◆ HashMap()

Member Function Documentation

◆ constBegin()

◆ constEnd()

◆ find()

◆ forEach()

◆ insert() [1/2]

◆ insert() [2/2]

◆ operator[]() [1/2]

◆ operator[]() [2/2]

◆ remove() [1/2]

◆ remove() [2/2]

◆ swap()

◆ value()