seqan3::detail::select_types_with_ids< field_types, field_types_as_ids, selected_field_ids, field_no, return_types > Struct Template Reference

Exposes a subset of types as a seqan3::type_list selected based on their IDs. More...

#include <seqan3/io/detail/record.hpp>

Inheritance diagram for seqan3::detail::select_types_with_ids< field_types, field_types_as_ids, selected_field_ids, field_no, return_types >:

Public Types
using	type = type_list< return_types... >
	The return type.

Related Symbols
(Note that these are not member symbols.)
template<typename field_types , typename field_types_as_ids , typename selected_field_ids , size_t field_no = 0, typename... return_types>
using	select_types_with_ids_t = typename select_types_with_ids< field_types, field_types_as_ids, selected_field_ids, field_no, return_types... >::type
	Shortcut for seqan3::select_types_with_ids (transformation_trait shortcut).

Detailed Description

template<typename field_types, typename field_types_as_ids, typename selected_field_ids, size_t field_no = 0, typename... return_types>
struct seqan3::detail::select_types_with_ids< field_types, field_types_as_ids, selected_field_ids, field_no, return_types >

Exposes a subset of types as a seqan3::type_list selected based on their IDs.

Template Parameters

field_types	The types of the fields available to the record in a seqan3::type_list.
field_types_as_ids	A seqan3::fields type with seqan3::field IDs corresponding to field_types.
selected_field_ids	A seqan3::fields type with the subset (and order) of the fields selected.
field_no	The field we are currently processing (defaults to 0).
return_types	The type pack being aggregated (empty at start).

Given a list of types and corresponding IDs; and given a selection (and possibly different order) of IDs, return the types corresponding to that selection and in that order.

This transformation trait recurses over the selected_field_ids and retrieves the corresponding typenames from field_types via their identifer in field_types_as_ids. It recursively builds up return_types which it packs into a seqan3::type_list once the end of selected_field_ids is reached.

Example

// SPDX-FileCopyrightText: 2006-2026 Knut Reinert & Freie Universität Berlin
// SPDX-FileCopyrightText: 2016-2026 Knut Reinert & MPI für molekulare Genetik
// SPDX-License-Identifier: CC0-1.0
 
#include <string>
#include <vector>
 
#include <seqan3/alphabet/nucleotide/dna4.hpp>
#include <seqan3/alphabet/quality/phred42.hpp>
#include <seqan3/io/detail/record.hpp>
#include <seqan3/utility/type_list/type_list.hpp>
 
int main()
{
    using types = seqan3::type_list<std::string, seqan3::dna4_vector, std::vector<seqan3::phred42>>;
    using types_as_ids = seqan3::fields<seqan3::field::id, seqan3::field::seq, seqan3::field::qual>;
    using selected_ids = seqan3::fields<seqan3::field::qual, seqan3::field::id>;
 
    using selected_types = seqan3::detail::select_types_with_ids_t<types, types_as_ids, selected_ids>;
    // resolves to type_list<std::vector<phred42>, std::string>
    static_assert(std::same_as<selected_types, seqan3::type_list<std::vector<seqan3::phred42>, std::string>>);
}

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

• detail/record.hpp