Porting Guide

How to port your code from seqan3::argument_parser to the sharg::parser

Update your seqan3 submodule

Go to the seqan3 submodules and update to current master (or release once seqan3 with sharg was released)

cd app/dir/lib/seqan3 # path where the seqan3submodule lives
git pull origin master
git submodule update --init

Now you should be able to use the sharg parser. You can test if it worked by including a sharg header without using it.

// somehwere inside a hpp or cpp file
#include <sharg/all.hpp>

Port your code

Namespace

Change the namespace of all argument parsing related entities from seqan3:: to sharg::.

Class renaming

The following classes have to be renamed:

• seqan3::argument_parser -> sharg::parser
• seqan3::argument_parser_error -> sharg::parser_error
• seqan3::argument_parsing -> sharg::parsing (CPO for customised option values, e.g. enumeration_names CPO)
• seqan3::argument_parser_compatible_option -> sharg::parser_compatible_option (concept, usually not used directly)

New add_[...] API

This will be the most work. Sorry for that, but we hope that it will be easier and more flexible in the future.

Instead of multiple parameters, the parser.add_[...] calls will take a value and a sharg::config object

Before:

parser.add_option(val, 'i', "int", "some int");

Now:

parser.add_option(val, sharg::config{.short_id = 'i', .long_id = "int", .description = "some int"});

here is a full config option for each add_[...]() call. You can adapt or delete the members you need

1. add_option

my_parser.add_option(my_value,
                     sharg::config{.short_id = 'i',
                                   .long_id = "int",
                                   .description = "some description.",
                                   .required = false,
                                   .advanced = false,
                                   .hidden = false,
                                   .validator = sharg::arithmetic_validator{0,2}});

2. add_flag

my_parser.add_flag(my_value,
                   sharg::config{.short_id = 'i',
                                 .long_id = "int",
                                 .description = "some description.",
                                 .advanced = false,
                                 .hidden = false);

3. add_positional_option

my_parser.add_positional_option(my_value,
                                sharg::config{.description = "some description.",
                                              .validator = sharg::arithmetic_validator{0,2}});

sharg::config API documentation is here. (Note that the documentation isn't detailed yet. It will become more detailed after feedback from you)