hash Namespace Reference

Hash functions. More...

Namespaces
	literals
	User-defined literals for compile-time string hashing.
	types
	Distinct hash value types for different hash algorithms.

Functions
template<std::unsigned_integral HashT, std::integral DataT>
constexpr HashT	fnv1a (std::span< const DataT > data, HashT offset, HashT prime) noexcept
	FNV-1a hash function. More...
template<std::integral DataT>
constexpr std::uint32_t	fnv1a32 (std::span< const DataT > data) noexcept
	32-bit FNV-1a hash function. More...
template<std::integral DataT>
constexpr std::uint64_t	fnv1a64 (std::span< const DataT > data) noexcept
	64-bit FNV-1a hash function. More...

Detailed Description

Hash functions.

Function Documentation

fnv1a()

template<std::unsigned_integral HashT, std::integral DataT>

constexpr HashT hash::fnv1a ( std::span< const DataT >  data, HashT  offset, HashT  prime  )

constexprnoexcept

FNV-1a hash function.

Template Parameters

HashT	Unsigned integral hash type.
DataT	Data element type.

Parameters

data	Array of data to hash.
offset	FNV offset basis value.
prime	FNV prime value.

Returns

Hash value.

See also

https://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function

@TODO reinterpret_cast is not supported in consteval. C++23 has if consteval which can selectively enable reinterpret_cast at runtime, and extract bytes manually at compile-time.

Definition at line 46 of file fnv1a.hpp.

fnv1a32()

template<std::integral DataT>

constexpr std::uint32_t hash::fnv1a32 ( std::span< const DataT >  data )

constexprnoexcept

32-bit FNV-1a hash function.

Template Parameters

DataT

Data element type.

Parameters

data	Array of data to hash.

Returns

32-bit FNV-1a hash value.

Definition at line 79 of file fnv1a.hpp.

fnv1a64()

template<std::integral DataT>

constexpr std::uint64_t hash::fnv1a64 ( std::span< const DataT >  data )

constexprnoexcept

64-bit FNV-1a hash function.

Template Parameters

DataT

Data element type.

Parameters

data	Array of data to hash.

Returns

64-bit FNV-1a hash value.

Definition at line 100 of file fnv1a.hpp.