clap4shell is a replacement for getopt based on clap.
clap4shell takes option descriptors as a YAML document from stdin, then prints the parsed result in newline-delimited key=value format which can be eval'd. See example.sh for concrete usage.
sh
nix profile install github:fumieval/clap4shell
Configurations look like
yaml
name: example
bin_name: $(basename $0)
version: "0.0"
about: sample text
author: Fumiaki Kinoshita <fumiexcel@gmail.com>
args:
- verbose:
help: verbose output
short: v
long: verbose
- host:
takes_value: true
long: host
value_name: <HOST>
help: 'host name'
- mode:
long: mode
help: option with a certain set of possible values
possible_values: [ herbivore, carnivore, omnivore ]
- cmd:
help: command
- arg:
help: command arguments
multiple_values: true
The schema is based on clap_serde.
The typical usage is to embed option definitions in a shell heredoc, pass all arguments to clap4shell and eval its output:
bash
eval "$(clap4shell parse "$@" <<EOT
...
EOT
)"
clap4shell-completion <shell> -o <path> subcommand generates an autocompletion script and writes the script to path.
sh
clap4shell clap4shell-completion bash -o ./bash-completion.sh < definition.yaml
Note that clap does not support completion for subcommands yet (clap panics for some reason)
I intentionally avoided using clap::App::from_yaml because the redundancy of the YAML representation and difficulty of debugging panics.
The YAML interface is being deprecated: https://github.com/clap-rs/clap/issues/3087