test_func_callout

#!/usr/bin/env bash
source mod_common
bi_enable


run_test()
{
    # variables external to callback function from which
    # values will be snagged.
    local -i ndx=0;
    local -a values=(
        first
        second
        third
        fourth
        fifth
        sixth
    )

    nested_function()
    {
        local -n nf_var="$1"
        local -n valarr="${2:-values}"

        if [ $ndx -lt "${#valarr[*]}" ]; then
            nf_var="${valarr[$ndx]}"
            (( ++ndx ))
            return 0
        fi

        return 1
    }



    echo "About to call ${B}func_callout${X} with a callback providing"
    echo "a set of english number names."
    echo
    func_callout "nested_function"

    echo
    echo "About to call ${B}func_callout${X} with a second parameter"
    echo "which will be transferred to the callback function to"
    echo "override the default array source of values."
    ndx=0
    local -a altarray=( un dos tres quatre cinq six )
    func_callout "nested_function" "altarray"

}

cat <<EOF
This tests a technique for a Bash builtin function to poll for
information from a shell script function.

The builtin function ${B}func_callout${X} will be called with
the name of a script function that the builtin can call.  The
callback function will provide a single value for each call,
transferred by setting the value of a nameref variable.

EOF

run_test