helios::utils::FolderFor Concept Reference

Concept for folder functions that accumulate values. More...

#include <functional_adapters.hpp>

Concept definition

template<typename Folder, typename Accumulator, typename ValueType>
concept helios::utils::FolderFor = 
    (std::invocable<Folder, Accumulator, ValueType> &&
     std::convertible_to<std::invoke_result_t<Folder, Accumulator, ValueType>, Accumulator>) ||
    (details::is_folder_applicable_v<Folder, Accumulator, std::remove_cvref_t<ValueType>> &&
     std::convertible_to<details::folder_apply_result_t<Folder, Accumulator, std::remove_cvref_t<ValueType>>,
                         Accumulator>)

Detailed Description

Concept for folder functions that accumulate values.

The function must be invocable with an accumulator and a value type. Supports both direct invocation and std::apply for tuple unpacking.

Template Parameters

Folder	Folder function type
Accumulator	Accumulator type
ValueType	Type of values to fold

Definition at line 181 of file functional_adapters.hpp.