FHashcode Struct Reference

Description:

This function returns a hashcode on contents of the box. This is useful if boxes are to be used as key-values of containers like std::unordered_map or HashTable.

Its default implementation creates a hash code using the raw placeholder values and in case of array types over the array memory used.

A templated version that compares the first N-bytes is given with UsePlaceholderBytes. Because the number of bytes to use are given with the template parameter, the method compiles to shortest code. It is registered with all fundamental types.

Note

Compatibility header alib/compatibility/std_boxing_functional.hpp specializes functors std::hash, std::equal_to and std::less for use with containers of the C++ standard library.

See also

Method Box::Hashcode, which calls this function.

Definition at line 74 of file functions.inl.

Public Type Index:
using	Signature = size_t (*) ( const Box& self )

Public Static Method Index:
template<size_t N>
static size_t	UsePlaceholderBytes (const Box &self)

Type Definition Details:

Signature

using Signature = size_t (*) ( const Box& self )

Signature of the invokable function.

Parameters

self	The box that the hash code is to be calculated for.

Returns

The hash code.

Definition at line 80 of file functions.inl.

Method Details:

UsePlaceholderBytes()

template<size_t N>

size_t UsePlaceholderBytes ( const Box & self )

static

Templated hash function usable with types boxed as values. For pointer types, a custom variant that collects type-specific hashable data is recommended.

Template Parameters

N	The number of bytes to check.

Parameters

self	The box to calculate a hash code for.

Returns

The hash code.

Definition at line 75 of file functiondefs.inl.

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

• functions.inl
• functiondefs.inl