SeqAn3 3.1.0
The Modern C++ library for sequence analysis.
seqan3::custom::argument_parsing< t > Struct Template Reference

A type that can be specialised to provide customisation point implementations for the seqan3::argument_parser such that third party types may be adapted. More...

#include <seqan3/argument_parser/auxiliary.hpp>

Detailed Description

template<typename t>
struct seqan3::custom::argument_parsing< t >

A type that can be specialised to provide customisation point implementations for the seqan3::argument_parser such that third party types may be adapted.

Template Parameters
tThe type you wish to specialise for.

Named Enumerations

In order to use a third party type within the seqan3::argument_parser::add_option or seqan3::argument_parser::add_positional_option call, you can specialise this struct in the following way:

#include <system_error>
namespace seqan3::custom
{
// Specialise the seqan3::custom::argument_parsing data structure to enable parsing of std::errc.
template <>
struct argument_parsing<std::errc>
{
// Specialise a mapping from an identifying string to the respective value of your type Foo.
{
{"no_error", std::errc{}},
{"timed_out", std::errc::timed_out},
{"invalid_argument", std::errc::invalid_argument},
{"io_error", std::errc::io_error}
};
};
} // namespace seqan3::custom
int main(int argc, char const * argv[])
{
std::errc value{};
seqan3::argument_parser parser{"my_program", argc, argv};
// Because of the argument_parsing struct and
// the static member function enumeration_names
// you can now add an option that takes a value of type std::errc:
parser.add_option(value, 'e', "errc", "Give me a std::errc value.", seqan3::option_spec::standard,
seqan3::value_list_validator{(seqan3::enumeration_names<std::errc> | std::views::values)});
try
{
parser.parse();
}
catch (seqan3::argument_parser_error const & ext) // the user did something wrong
{
std::cerr << "[PARSER ERROR] " << ext.what() << "\n"; // customize your error message
return -1;
}
return 0;
}
Meta-header for the Argument Parser module .
Argument parser exception that is thrown whenever there is an error while parsing the command line ar...
Definition: exceptions.hpp:40
The SeqAn command line parser.
Definition: argument_parser.hpp:154
void add_option(option_type &value, char const short_id, std::string const &long_id, std::string const &desc, option_spec const spec=option_spec::standard, validator_type option_validator=validator_type{})
Adds an option to the seqan3::argument_parser.
Definition: argument_parser.hpp:247
A validator that checks whether a value is inside a list of valid values.
Definition: validators.hpp:198
auto const enumeration_names
Return a conversion map from std::string_view to option_type.
Definition: auxiliary.hpp:165
@ standard
The default were no checking or special displaying is happening.
Definition: auxiliary.hpp:250
A namespace for third party and standard library specialisations of SeqAn customisation points.
Definition: char.hpp:44
SeqAn specific customisations in the standard namespace.
The <ranges> header from C++20's standard library.
T what(T... args)

Please note that by default the t const, t & and t const & specialisations of this class inherit the specialisation for t so you usually only need to provide a specialisation for t.

Note
Only use this if you cannot provide respective functions in your namespace. See the tutorial Parsing command line arguments with SeqAn for an example of customising a type within your own namespace.
Remarks
For a complete overview, take a look at Argument Parser

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