try_argparser.sh

#!/usr/bin/env bash

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#                                                                             #
# Copyright 2025 Simon Brandt                                                 #
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# Licensed under the Apache License, Version 2.0 (the "License");             #
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# Unless required by applicable law or agreed to in writing, software         #
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# Author: Simon Brandt
# E-Mail: simon.brandt@uni-greifswald.de
# Last Modification: 2025-09-01

# Usage: Run this script with "bash try_argparser.sh".

# Purpose: Demonstrate the basic functionality of the Argparser.

# Define the arguments.
# shellcheck disable=SC2190  # Indexed, not associative array.
args=(
    "id    | short_opts | long_opts   | val_names | defaults | choices | type | arg_no | arg_group            | notes      | help                                              "
    "pos_1 |            |             | pos_1     | 2        | 1,2     | int  | 1      | Positional arguments |            | one positional argument with default and choice   "
    "pos_2 |            |             | pos_2     |          |         | int  | 2      | Positional arguments |            | two positional arguments without default or choice"
    "var_1 | a,A        | var-1,var-a | VAL_1     |          |         | uint | 1      | Mandatory options    |            | one value without default or choice               "
    "var_2 | b,B        | var-2,var-b | VAL_2     |          |         | int  | +      | Mandatory options    |            | at least one value without default or choice      "
    "var_3 | c,C        | var-3,var-c | VAL_3     |          | A,B     | char | +      | Mandatory options    |            | at least one value with choice                    "
    "var_4 | d,D        | var-4,var-d | VAL_4     | A        | A-C     | char | 1      | Optional options     |            | one value with default and choice                 "
    "var_5 | e,E        | var-5,var-e | VAL_5     | E        |         | str  | 1      | Optional options     |            | one value with default                            "
    "var_6 | f,F        | var-6,var-f | VAL_6     | false    |         | bool | 0      | Optional options     |            | no value (flag) with default                      "
    "var_7 | g,G        | var-7,var-g | VAL_7     | true     |         | bool | 0      | Optional options     | deprecated | no value (flag) with default                      "
)
source argparser -- "$@"

# The arguments can now be accessed as keys and values of the
# associative array "args".  Further, they are set as variables to the
# environment, from which they are expanded by globbing.
for arg in "${!var@}"; do
    printf 'The keyword argument "%s" is set to "%s".\n' \
        "${arg}" "${args[${arg}]}"
done | sort

index=1
for arg in "${!pos@}"; do
    printf 'The positional argument "%s" on index %s is set to "%s".\n' \
        "${arg}" "${index}" "${args[${arg}]}"
    (( index++ ))
done