Re: [Help-bash] The best way to get the last element of $@

[Dan Douglas]

On Fri, Mar 20, 2015 at 5:25 PM, Dan Douglas <address@hidden> wrote:
> Greg's way is fine but inefficient and non-portable.

Actually the first way is quite portable (unless you use a bad shell
that lacks local). String subscripting a bit less so, especially for `@'.

Also of course I screwed up my quoting copying from an interactive
shell...

    #!/usr/bin/env bash

    set foo bar

    if ! ${BASH_VERSION+false}; then
        # this only works in bash, but is still more portable than printf -v
        last=${!#}
    elif ! ${KSH_VERSION+false}; then
        if [[ ${!KSH_VERSION} == .sh.version ]]; then
            # Almighty hack to peek at caller's parameters.
            function last.get {
                trap 'trap - DEBUG; ((.sh.level--)); eval
".sh.value=\$${#}\${ let .sh.level++; }"' DEBUG
                :
            }
        else
            # mksh makes the obvious thing that SHOULD work everywhere actually
            # work. Sadly, it can't dereference `#' a second time so
it's still not
            # dynamic.
            nameref last=$#
        fi
    else
        # For random shells.
        eval last=\$$#
    fi

    # set -ft last.get
    echo "$last"

-- 
Dan Douglas