SeqAn3  3.0.1
The Modern C++ library for sequence analysis.
seqan3::pack_traits Namespace Reference

Namespace containing traits for working on type packs. More...

Typedefs

Type pack traits (return a single type)
template<ptrdiff_t idx, typename ... pack_t>
using at = typename decltype(detail::at< idx, pack_t... >())::type
 Return the type at given index from the type pack. More...
 
template<typename ... pack_t>
using front = typename decltype(detail::front< pack_t... >())::type
 Return the first type from the type pack. More...
 
template<typename ... pack_t>
using back = typename decltype((std::type_identity< pack_t >{},...))::type
 Return the last type from the type pack. More...
 
Type pack traits (return a type list)
template<typename ... pack_t>
using drop_front = typename decltype(detail::drop_front< pack_t... >())::type
 Return a seqan3::type_list of all the types in the type pack, except the first. More...
 
template<template< typename > typename trait_t, typename ... pack_t>
using transform = seqan3::type_list< trait_t< pack_t >... >
 Apply a transformation trait to every type in the pack and return a seqan3::type_list of the results. More...
 
template<ptrdiff_t i, typename ... pack_t>
using take = seqan3::list_traits::take< i, type_list< pack_t... > >
 Return a seqan3::type_list of the first n types in the type pack. More...
 
template<ptrdiff_t i, typename ... pack_t>
using drop = seqan3::list_traits::drop< i, type_list< pack_t... > >
 Return a seqan3::type_list of the types in the type pack, except the first n. More...
 
template<ptrdiff_t i, typename ... pack_t>
using take_last = seqan3::list_traits::take_last< i, type_list< pack_t... > >
 Return a seqan3::type_list of the last n types in the type pack. More...
 
template<ptrdiff_t i, typename ... pack_t>
using drop_last = seqan3::list_traits::drop_last< i, type_list< pack_t... > >
 Return a seqan3::type_list of the types the type pack, except the last n. More...
 
template<ptrdiff_t i, typename ... pack_t>
using split_after = seqan3::list_traits::split_after< i, type_list< pack_t... > >
 Split a type pack into two parts returned as a pair of seqan3::type_list. More...
 
template<typename replace_t , std::ptrdiff_t i, typename ... pack_t>
using replace_at = decltype(seqan3::list_traits::replace_at< replace_t, i, type_list< pack_t... > >())
 Replace the type at the given index with the given type. More...
 

Variables

Type pack traits (return a value)
template<typename ... pack_t>
constexpr size_t size = sizeof...(pack_t)
 The size of a type pack. More...
 
template<typename query_t , typename ... pack_t>
constexpr ptrdiff_t count = (SEQAN3_IS_SAME(query_t, pack_t) + ... + 0)
 Count the occurrences of a type in a pack. More...
 
template<typename query_t , typename ... pack_t>
constexpr ptrdiff_t find = seqan3::pack_traits::detail::find<query_t, pack_t...>()
 Get the index of the first occurrence of a type in a pack. More...
 
template<template< typename > typename pred_t, typename ... pack_t>
constexpr ptrdiff_t find_if = seqan3::pack_traits::detail::find_if<pred_t, pack_t...>()
 Get the index of the first type in a pack that satisfies the given predicate. More...
 
template<typename query_t , typename ... pack_t>
constexpr bool contains = (find<query_t, pack_t...> != -1)
 Whether a type occurs in a pack or not. More...
 

Detailed Description

Namespace containing traits for working on type packs.