flags_details_ex

#!/bin/bash
#
# Command line flag parsing and use of those flags.

readonly DIR=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
. ${DIR}/../gobash


# Checking if argument values are as expected has to be done by
# developers explicitly like in this function.
function check_arguments() {
        local -r args="${1}"
        shift 1

        # Just for fun, we require that --ignore is set.
        if is_false "$($args ignore)"; then
                echo "'ignore' has to be set."
                return $EC
        fi
}

# The following function is some random computation to illustrate how
# code for parsing can be connected to other/existing code.
function compute_loc() {
        local -r url="${1}"
        shift 1

        # Clone the repository into a random dir and get number of
        # lines of code.
        local tmpd=$(os_mktemp_dir)
        echo ${tmpd}
        git clone ${url} ${tmpd}
        cloc ${tmpd} | grep 'SUM:' | $X_AWK '{ print $5 }'
}

function main() {
        # Create an instance of flags, then add desired flags.
        flags=$(Flags "Example of parsing arguments.")
        $flags add "$(Flag ignore $BOOL 'An argument that has to be set for fun.')"
        $flags add "$(Flag max $INT 'Max number of repos to use.')"

        # Create object that will contain values.
        local -r args=$(Args)
        # Create context.
        local -r ctx=$(ctx_make)

        # Parse then check for errors.
        $flags $ctx parse "$args" "$@" || \
                { ctx_show $ctx; $flags help; return $EC; }

        # Invoke a method to check if arguments are valid.
        check_arguments "$args" || return $EC

        # Code below has access to arguments via the `args` instance.

        local -r repos=$(Map)
        $repos put "math" "https://github.com/apache/commons-math"
        $repos put "io" "https://github.com/apache/commons-io"

        local -r keys=$($repos keys)

        local i
        for (( i=0; i<$($keys len); i++ )); do
                # We ensure not to exceed the max number of URLs to
                # process, which can be provided as a command line
                # argument (--max).
                [ ${i} = $($args max) ] && break
                local key=$($keys get $i)
                compute_loc $($repos get "$key")
        done
}

main "$@"