argparse
Build command-line interfaces declaratively. Produces help and usage strings, parses values, dispatches subcommands.
Source-of-record: Lib/argparse.py,
argparse docs.
ArgumentParser
ArgumentParser(prog=None, usage=None, description=None, epilog=None, parents=[], formatter_class=HelpFormatter, prefix_chars='-', fromfile_prefix_chars=None, argument_default=None, conflict_handler='error', add_help=True, allow_abbrev=True, exit_on_error=True, suggest_on_error=False) (3.14+ adds suggest_on_error).
| Method | Purpose |
|---|---|
add_argument(...) | Register flag / positional. |
add_subparsers(...) | Subcommand container. |
add_argument_group(title=None, description=None) | Group for help. |
add_mutually_exclusive_group(required=False) | XOR group. |
parse_args(args=None, namespace=None) | Parse. |
parse_known_args(...) | Partial parse. |
parse_intermixed_args(...) / parse_known_intermixed_args(...) | Positional-after-optional support. |
set_defaults(**kw) | Inject defaults. |
format_help() / format_usage() / print_help() / print_usage() | Help text. |
error(msg) / exit(status=0, message=None) | Exit hooks. |
add_argument parameters
name_or_flags, action, nargs, const, default, type,
choices, required, help, metavar, dest, version,
deprecated (3.13+).
Built-in actions
store, store_const, store_true, store_false, append,
append_const, count, help, version, extend,
BooleanOptionalAction (3.9+).
Types
Pass any callable; common helpers: int, float,
argparse.FileType('r'). BooleanOptionalAction emits paired
--flag / --no-flag.
Formatters
HelpFormatter, RawDescriptionHelpFormatter,
RawTextHelpFormatter, ArgumentDefaultsHelpFormatter,
MetavarTypeHelpFormatter.
Subparsers
add_subparsers(title=None, description=None, prog=None, parser_class=ArgumentParser, action=None, dest=None, required=False, help=None, metavar=None).
Sub-parsers can have their own defaults and parents.
Gopy status
| Area | State |
|---|---|
| Core parser, all actions | Complete. |
| Subparsers, parents, groups | Complete. |
parse_intermixed_args | Complete. |
BooleanOptionalAction | Complete. |
suggest_on_error (3.14) | Complete. |
Reference
- CPython 3.14: argparse.
Lib/argparse.py.module/argparse/. gopy port.