#!/usr/bin/env bash
# compat: -ash +bash -dash +zsh

is_empty() { ### @-
    ### return 0 if the directory given by argument is empty.
    while read -r f; do
        [ ! -d "$f" ] && [ -s "$f" ] && return 1
    done < <(find ${1:-.})
    # TODO: done < <(find ${1:-.} -type f -print -quit)
    # this needs to skip empty files as well.
    return 0
}

[ -n "${preload+-}" ] || is_empty "$@"