seqan3::search_cfg::on_result< callback_t > Class Template Reference

Configuration element to provide a user defined callback function for the search. More...

#include <seqan3/search/configuration/on_result.hpp>

Inheritance diagram for seqan3::search_cfg::on_result< callback_t >:

Public Member Functions
Constructors, destructor and assignment
constexpr	on_result ()=default
	Defaulted.
constexpr	on_result (on_result const &)=default
	Defaulted.
constexpr	on_result (on_result &&)=default
	Defaulted.
constexpr on_result &	operator= (on_result const &)=default
	Defaulted.
constexpr on_result &	operator= (on_result &&)=default
	Defaulted.
	~on_result ()=default
	Defaulted.
constexpr	on_result (callback_t &&callback)
	Constructs the configuration element with the given user callback.

Public Attributes
seqan::stl::detail::movable_box_t< callback_t >	callback
	The stored callable which will be invoked with the search result.

Static Private Attributes
static constexpr seqan3::detail::search_config_id	id {seqan3::detail::search_config_id::on_result}
	Internal id to check for consistent configuration settings.

Detailed Description

template<std::move_constructible callback_t>
class seqan3::search_cfg::on_result< callback_t >

Configuration element to provide a user defined callback function for the search.

See also

Configuration

Template Parameters

callback_t

The type of the callback; must model std::invocable with the generated seqan3::search_result and std::move_constructible.

Allows the user to specify a callback that should be called for every computed search result. The callback must take exactly one argument for the search result and return void. If the user callback is specified, the call to the search algorithm seqan3::search will return nothing, i.e. it does not return a seqan3::algorithm_result_generator_range any more. Note that within a parallel configuration, the order of the generated search results and therefore the call to the user callback is non-deterministic. However, the continuation interface with the user callback can be more efficient in a concurrent environment.

The given callback is wrapped inside a seqan::stl::detail::movable_box wrapper type. This allows to also use lambdas with a capture block, which otherwise are not std::copy_assignable and therefore invalidate the requirements for the configuration element (must model std::semiregular).

Example

The following code snippet demonstrates the basic usage:

// SPDX-FileCopyrightText: 2006-2025 Knut Reinert & Freie Universität Berlin
// SPDX-FileCopyrightText: 2016-2025 Knut Reinert & MPI für molekulare Genetik
// SPDX-License-Identifier: CC0-1.0
 
#include <seqan3/core/debug_stream.hpp>
#include <seqan3/search/configuration/on_result.hpp>
 
int main()
{
    seqan3::search_cfg::on_result cfg{[](auto && result)
                                      {
                                          seqan3::debug_stream << result << '\n';
                                      }};
    return 0;
}

Constructor & Destructor Documentation

on_result()

template<std::move_constructible callback_t>

constexpr seqan3::search_cfg::on_result< callback_t >::on_result ( callback_t &&  callback )

inlineexplicitconstexpr

Constructs the configuration element with the given user callback.

Parameters

[in]

callback

The callback to invoke with a computed seqan3::search_result.

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

• on_result.hpp