dpp::snowflake Class Reference

A container for a 64 bit unsigned value representing many things on discord. This value is known in distributed computing as a snowflake value. More...

#include <snowflake.h>

Collaboration diagram for dpp::snowflake:

Public Member Functions
constexpr	snowflake () noexcept=default
	Construct a snowflake object. More...
constexpr	snowflake (const snowflake &rhs) noexcept=default
	Copy a snowflake object. More...
template<typename T , typename = std::enable_if_t<std::is_same_v<T, std::string>>>
	snowflake (const T &string_value) noexcept
	Construct a snowflake object from an unsigned integer in a string. More...
constexpr	snowflake (snowflake &&rhs) noexcept=default
	Move a snowflake object. More...
	snowflake (std::string_view string_value) noexcept
	Construct a snowflake object from an unsigned integer in a string. More...
template<typename T , typename = std::enable_if_t<std::is_integral_v<T> && !std::is_same_v<T, bool>>>
constexpr	snowflake (T snowflake_val) noexcept(std::is_unsigned_v< T >)
	Construct a snowflake from an integer value. More...
constexpr bool	empty () const noexcept
	Returns true if the snowflake holds an empty value (is 0) More...
constexpr double	get_creation_time () const noexcept
	Get the creation time of this snowflake according to Discord. More...
constexpr uint16_t	get_increment () const noexcept
	Get the increment, which is incremented for every snowflake created over the one millisecond resolution in the timestamp. More...
constexpr uint8_t	get_process_id () const noexcept
	Get the process id that produced this snowflake value. More...
constexpr uint8_t	get_worker_id () const noexcept
	Get the worker id that produced this snowflake value. More...
	operator json () const
	For building json. More...
constexpr	operator uint64_t () const noexcept
	For acting like an integer. More...
constexpr	operator uint64_t & () noexcept
	For acting like an integer. More...
constexpr dpp::snowflake &	operator= (const dpp::snowflake &rhs) noexcept=default
	Copy value from another snowflake. More...
constexpr dpp::snowflake &	operator= (dpp::snowflake &&rhs) noexcept=default
	Move value from another snowflake. More...
template<typename T , typename = std::enable_if_t<std::is_convertible_v<T, std::string_view>>>
constexpr dpp::snowflake &	operator= (T &&snowflake_val) noexcept
	Assign value converted from a string to the snowflake. More...
template<typename T , typename = std::enable_if_t<std::is_integral_v<T>>>
constexpr dpp::snowflake &	operator= (T snowflake_val) noexcept(std::is_unsigned_v< T >)
	Assign integer value to the snowflake. More...
constexpr bool	operator== (dpp::snowflake snowflake_val) const noexcept
	Comparison operator with another snowflake. More...
bool	operator== (std::string_view snowflake_val) const noexcept
	Comparison operator with a string. More...
template<typename T , typename = std::enable_if_t<std::is_integral_v<T>>>
constexpr bool	operator== (T snowflake_val) const noexcept
	Comparison operator with an integer. More...
std::string	str () const
	Returns the stringified version of the snowflake value. More...

Protected Attributes
uint64_t	value = 0
	The snowflake value. More...

Friends
constexpr friend uint64_t	format_as (snowflake s) noexcept
	Helper function for libfmt so that a snowflake can be directly formatted as a uint64_t. More...
struct	std::hash< dpp::snowflake >

Detailed Description

A container for a 64 bit unsigned value representing many things on discord. This value is known in distributed computing as a snowflake value.

Snowflakes are:

• Performant (very fast to generate at source and to compare in code)
• Uncoordinated (allowing high availability across clusters, data centres etc)
• Time ordered (newer snowflakes have higher IDs)
• Directly Sortable (due to time ordering)
• Compact (64 bit numbers, not 128 bit, or string)

An identical format of snowflake is used by Twitter, Instagram and several other platforms.

See also

https://en.wikipedia.org/wiki/Snowflake_ID

https://github.com/twitter-archive/snowflake/tree/b3f6a3c6ca8e1b6847baa6ff42bf72201e2c2231

Constructor & Destructor Documentation

snowflake() [1/6]

constexpr dpp::snowflake::snowflake ( )

constexprdefaultnoexcept

Construct a snowflake object.

snowflake() [2/6]

constexpr dpp::snowflake::snowflake ( const snowflake &  rhs )

constexprdefaultnoexcept

Copy a snowflake object.

snowflake() [3/6]

constexpr dpp::snowflake::snowflake ( snowflake &&  rhs )

constexprdefaultnoexcept

Move a snowflake object.

snowflake() [4/6]

template<typename T , typename = std::enable_if_t<std::is_integral_v<T> && !std::is_same_v<T, bool>>>

constexpr dpp::snowflake::snowflake ( T  snowflake_val )

inlineconstexprnoexcept

Construct a snowflake from an integer value.

Exceptions

dpp::logic_exception

on assigning a negative value. The function is noexcept if the type given is unsigned

Parameters

snowflake_val

snowflake value as an integer type

we cast to the unsigned version of the type given - this maintains "possible loss of data" warnings for sizeof(T) > sizeof(value) while suppressing them for signed to unsigned conversion (for example snowflake(42) will call snowflake(int) which is a signed type)

snowflake() [5/6]

dpp::snowflake::snowflake ( std::string_view  string_value )

noexcept

Construct a snowflake object from an unsigned integer in a string.

On invalid string the value will be 0

Parameters

string_value

A snowflake value

snowflake() [6/6]

template<typename T , typename = std::enable_if_t<std::is_same_v<T, std::string>>>

dpp::snowflake::snowflake ( const T &  string_value )

inlinenoexcept

Construct a snowflake object from an unsigned integer in a string.

On invalid string the value will be 0

Parameters

string_value

A snowflake value

Member Function Documentation

empty()

constexpr bool dpp::snowflake::empty ( ) const

inlineconstexprnoexcept

Returns true if the snowflake holds an empty value (is 0)

Returns

true if empty (zero)

get_creation_time()

constexpr double dpp::snowflake::get_creation_time ( ) const

inlineconstexprnoexcept

Get the creation time of this snowflake according to Discord.

Returns

double creation time inferred from the snowflake ID. The minimum possible value is the first second of 2015.

get_increment()

constexpr uint16_t dpp::snowflake::get_increment ( ) const

inlineconstexprnoexcept

Get the increment, which is incremented for every snowflake created over the one millisecond resolution in the timestamp.

Returns

uint64_t millisecond increment

get_process_id()

constexpr uint8_t dpp::snowflake::get_process_id ( ) const

inlineconstexprnoexcept

Get the process id that produced this snowflake value.

Returns

uint8_t process id

get_worker_id()

constexpr uint8_t dpp::snowflake::get_worker_id ( ) const

inlineconstexprnoexcept

Get the worker id that produced this snowflake value.

Returns

uint8_t worker id

operator json()

dpp::snowflake::operator json

(

)

const

For building json.

Returns

The snowflake value as a string

operator uint64_t()

constexpr dpp::snowflake::operator uint64_t ( ) const

inlineconstexprnoexcept

For acting like an integer.

Returns

The snowflake value

operator uint64_t &()

constexpr dpp::snowflake::operator uint64_t & ( )

inlineconstexprnoexcept

For acting like an integer.

Returns

A reference to the snowflake value

operator=() [1/4]

constexpr dpp::snowflake & dpp::snowflake::operator= ( const dpp::snowflake &  rhs )

constexprdefaultnoexcept

Copy value from another snowflake.

Parameters

rhs	The snowflake to copy from

operator=() [2/4]

constexpr dpp::snowflake & dpp::snowflake::operator= ( dpp::snowflake &&  rhs )

constexprdefaultnoexcept

Move value from another snowflake.

Parameters

rhs	The snowflake to move from

operator=() [3/4]

template<typename T , typename = std::enable_if_t<std::is_convertible_v<T, std::string_view>>>

constexpr dpp::snowflake & dpp::snowflake::operator= ( T &&  snowflake_val )

inlineconstexprnoexcept

Assign value converted from a string to the snowflake.

On invalid string the value will be 0

Parameters

snowflake_val

snowflake value as a string

operator=() [4/4]

template<typename T , typename = std::enable_if_t<std::is_integral_v<T>>>

constexpr dpp::snowflake & dpp::snowflake::operator= ( T  snowflake_val )

inlineconstexprnoexcept

Assign integer value to the snowflake.

Exceptions

dpp::logic_exception

on assigning a negative value. The function is noexcept if the type given is unsigned

Parameters

snowflake_val

snowflake value as an integer type

operator==() [1/3]

constexpr bool dpp::snowflake::operator== ( dpp::snowflake  snowflake_val ) const

inlineconstexprnoexcept

Comparison operator with another snowflake.

Parameters

snowflake_val

snowflake

operator==() [2/3]

bool dpp::snowflake::operator== ( std::string_view  snowflake_val ) const

noexcept

Comparison operator with a string.

Parameters

snowflake_val

snowflake value as a string

operator==() [3/3]

template<typename T , typename = std::enable_if_t<std::is_integral_v<T>>>

constexpr bool dpp::snowflake::operator== ( T  snowflake_val ) const

inlineconstexprnoexcept

Comparison operator with an integer.

Parameters

snowflake_val

snowflake value as an integer type

str()

std::string dpp::snowflake::str ( ) const

inline

Returns the stringified version of the snowflake value.

Returns

std::string string form of snowflake value

Friends And Related Function Documentation

format_as

constexpr friend uint64_t format_as ( snowflake  s )

friend

Helper function for libfmt so that a snowflake can be directly formatted as a uint64_t.

See also

https://fmt.dev/latest/api.html#formatting-user-defined-types

Returns

uint64_t snowflake ID

std::hash< dpp::snowflake >

friend struct std::hash< dpp::snowflake >

friend

Member Data Documentation

value

uint64_t dpp::snowflake::value = 0

protected

The snowflake value.