Support for positional arguments

[cweagans]

I have a command that can be invoked like so:

my_command --foo=bar "first_arg" "second_arg"

(first_arg and second_arg are arbitrary strings)

My parser definition looks like this:

parser_definition() {
  setup ARGS
  param FOO --foo
}
eval "$(getoptions parser_definition __parse) exit 1"
__parse "$@"

echo "$FOO"

That all works great, but then I need to do something like this for the remaining positional arguments:

parse_args() {
  local var_names=("$@")
  local i=0
  for arg in $ARGS; do
    echo export ${var_names[$i]}="$arg"
    i=$((i + 1))
  done
}

eval "$(parse_args "FIRST" "SECOND")"

echo $FIRST         # outputs "first_arg"
echo $SECOND    # outputs "second_arg"

Do you think it makes sense to add a new kind of argument to the parser_definition where I can define the positional arguments too? Maybe something along these lines:

parser_definition() {
  setup ARGS
  param FOO --foo
  arg MY_ARG
  arg ANOTHER_ARG
}

I imagine that this could filter $@ to elements that do not begin with a - or --, and then $MY_ARG is assigned the value of the first arg, $ANOTHER_ARG is assigned the value of the second arg, and so forth.

There are probably other considerations for this library, but as a starting point, does this idea make sense and/or would you be interested in a PR to add something like that?

[ko1nksm]

It should be able to be written as follows

parser_definition() {
  setup ARGS
  param FOO --foo
}
eval "$(getoptions parser_definition __parse) exit 1"
__parse "$@"
eval "set -- $ARGS" # 👈

echo "$FOO"

FIRST="$1" SECOND="$2"

echo $FIRST         # outputs "first_arg"
echo $SECOND    # outputs "second_arg"

It could be simplified a bit more and written as follows

parser_definition() {
  setup ARGS
  param FOO --foo
}
eval "$(getoptions parser_definition) exit 1"
echo "$FOO"

FIRST="$1" SECOND="$2"

echo $FIRST         # outputs "first_arg"
echo $SECOND    # outputs "second_arg"

Perhaps documentation needs to be improved.

[cweagans]

Right. I'm saying that it would be nicer if the positional args could be defined in the same parser definition function (and have the positional args loaded into the right vars), rather than doing extra stuff after calling __parse