備忘録: 最小限の労力でサブコマンド付きのシェルスクリプトが書きたい ref: http://qiita.com/kitsuyui/items/4b204963e0ebec53fe3c

file0.txt

$ some-command
Usage:
  some-command --help
  some-command sub-command1
  some-command sub-command2

file1.txt

$ some-command --help
Usage:
  some-command --help
  some-command sub-command1
  some-command sub-command2

file2.txt

$ some-command sub-command1
1
$ some-command sub-command2
2

file3.txt

$ some-command wrong-command
Usage:
  some-command --help
  some-command sub-command1
  some-command sub-command2
$ echo $?
1

file5.txt

unset -f -- "${FUNCNAME[0]}"

file6.txt

compgen -A function \
    | xargs -I % echo ' ' "$(basename "$0")" %

file7.txt

  ! declare -F -- "$1" >/dev/null && --help && exit 1

file8.txt

sub-command1() {
  echo "$@"
}

file9.txt

$ some-command sub-command1 A B C
A B C

some-command

#!/usr/bin/env bash
sub-command1() {
  echo 1
}

sub-command2() {
  echo 2
}

--help() {
  echo 'Usage:'
  compgen -A function \
    | xargs -I % echo ' ' "$(basename "$0")" %
}

main() {
  unset -f -- "${FUNCNAME[0]}"
  ! declare -F -- "$1" >/dev/null && --help && exit 1
  "$@"
}

main "$@"

ここはコピペ

# http://qiita.com/kitsuyui/items/4b204963e0ebec53fe3c

--help() {
  echo 'Usage:'
  compgen -A function \
    | xargs -I % echo ' ' "$(basename "$0")" %
}

main() {
  unset -f -- "${FUNCNAME[0]}"
  ! declare -F -- "$1" >/dev/null && --help && exit 1
  "$@"
}

main "$@"