Scine::Molassembler::Temple::TinyUnorderedSet< T > Struct Template Reference

An adapter class for std::vector that acts like an unordered set and stores its data in the underlying vector in an unordered fashion. More...

#include <TinySet.h>

Public Types
Types
using	UnderlyingContainer = std::vector< T >
	The type of the underlying container with linear memory.
using	value_type = T
	What types this container stores.
using	reference = T &
	Reference to a value_type.
using	const_reference = const T &
	Const reference to a value type.
using	iterator = typename std::vector< T >::iterator
	Iterator type.
using	const_iterator = typename std::vector< T >::const_iterator
	Const iterator type.

Public Member Functions
Constructors
	TinyUnorderedSet ()
	Default constructor.
	TinyUnorderedSet (std::initializer_list< T > list)
	Initializer-list constructor.
Modification
void	clear ()
	Empties the set.
void	insert (T a)
	Inserts an element into the set. More...
template<typename... Args>
void	emplace (Args &&...args)
	Emplaces an element into the set. More...
template<typename It >
void	erase (It a)
	Erases a position in the set.
template<typename It >
void	insert (It a, const It &b)
	Inserts all elements contained in a range.
void	reserve (std::size_t size)
	Reserves space in memory.
Information
unsigned	count (T a) const
	Counts the number of occurrences of an element.
std::size_t	size () const
	Returns the number of elements in the set.
bool	empty () const
	Returns whether the set is empty.
Iterators
iterator	begin ()
	Yields a begin iterator.
iterator	end ()
	Yields an end iterator.
const_iterator	begin () const
	Yields a begin const iterator.
const_iterator	end () const
	Yields an end const iterator.
const_iterator	cbegin () const
	Yields a begin const iterator.
const_iterator	cend () const
	Yields an end const iterator.

Static Public Member Functions
Static functions
static bool	checked_insert (std::vector< T > &set, T a)
	Inserts an element only if the element is not already in the set. More...
template<typename... Args>
static void	checked_emplace (std::vector< T > &set, Args &&...args)
	Checked emplace of an element into a set. More...
static bool	linear_search (std::vector< T > &set, const T &value)
	Linear search for a value. More...

Data Fields
State
UnderlyingContainer	data
	The owned underlying linear memory container.

Detailed Description

template<typename T>
struct Scine::Molassembler::Temple::TinyUnorderedSet< T >

An adapter class for std::vector that acts like an unordered set and stores its data in the underlying vector in an unordered fashion.

Why? It's a lot simpler / smaller than unordered_set and seems to be faster for very small amounts of data. Break-even with an unordered_set for finding a value is at around N = 80 for numeric types, although I certainly do not trust the benchmark much.

Template Parameters

The	set value type

Member Function Documentation

template<typename T >

template<typename... Args>

static void Scine::Molassembler::Temple::TinyUnorderedSet< T >::checked_emplace ( std::vector< T > &  set, Args &&...  args  )

inlinestatic

Checked emplace of an element into a set.

In-place constructs a T, then checks if it already exists in the set. If it does, it is removed again.

Template Parameters

Args	Parameter pack to forward to T's constructor

Parameters

set	Set to insert the element into
args	Arguments to forward to T's constructor

template<typename T >

static bool Scine::Molassembler::Temple::TinyUnorderedSet< T >::checked_insert ( std::vector< T > &  set, T  a  )

inlinestatic

Inserts an element only if the element is not already in the set.

Parameters

set	Set to insert the element into
a	Element to insert

Returns

Whether the element was already in the set

template<typename T >

template<typename... Args>

void Scine::Molassembler::Temple::TinyUnorderedSet< T >::emplace ( Args &&...  args )

inline

Emplaces an element into the set.

Note

You can use this just like std::vector::emplace_back

Warning

This does not check if the element already exists

template<typename T >

void Scine::Molassembler::Temple::TinyUnorderedSet< T >::insert ( T  a )

inline

Inserts an element into the set.

Warning

This does not check if the element already exists.

template<typename T >

static bool Scine::Molassembler::Temple::TinyUnorderedSet< T >::linear_search ( std::vector< T > &  set, const T &  value  )

inlinestatic

Linear search for a value.

Parameters

set	Set to search
value	Value to look for

Returns

Whether the value was found

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

• Molassembler/Temple/TinySet.h