rc/sh/preload

#!/usr/bin/env false

preload() { ### @- handle dependencies within the [`~/sh/`](/sh) directory.
    ### this function contains more comments than code, so you should read it.
    # all sourced files from within the preload function will instead
    # append to the list of files to preload (i.e. dependencies).
    # dash and ash have no arrays besides $@, so we must use it.
    local preload='set -- $@'
    # we want to iterate over $@ like a queue; pushing and popping.
    # `for` would create a local copy and leave $@ unmodified, so it's no good.
    while [ $# -gt 0 ]; do
        # NOTE: there's no quotes here since the surrounding method uses eval,
        #       so paths-with-spaces is already doomed from the start.
        #       however, $HOME can still safely contain spaces.
        # NOTE: it's important to use an absolute path here.
        . ~/sh/$1 # yes, you can source files from within functions,
                  # and they even respect your locals.
        [ $? -eq 0 ] \
        || exit 2 # this `exit 2` is just for zsh and bash;
                  # dash and ash do it automatically.
                  # zsh actually uses some other return value,
                  # but we use 2 anyway since everything else uses 2.
        shift # pop the queue
    done
}