vcs_info () { # {{{
    local pat
    local -i found
    local -a VCSs disabled dps
    local -x vcs usercontext
    local -ix maxexports
    local -ax msgs
    local -Ax vcs_comm

    vcs="init"
    VCSs=(git hg bzr darcs svk mtn svn cvs cdv tla)
    case $1 in
        (print_systems_)
            zstyle -a ":vcs_info:${vcs}:${usercontext}" "disable" disabled
            print -l '# list of supported version control backends:' \
                     '# disabled systems are prefixed by a hash sign (#)'
            for vcs in ${VCSs} ; do
                [[ -n ${(M)disabled:#${vcs}} ]] && printf '#'
                printf '%s\n' ${vcs}
            done
            print -l '# flavours (cannot be used in the disable style; they' \
                     '# are disabled with their master [git-svn -> git]):'   \
                     git-{p4,svn}
            return 0
            ;;
        ('')
            [[ -z ${usercontext} ]] && usercontext=default
            ;;
        (*) [[ -z ${usercontext} ]] && usercontext=$1
            ;;
    esac

    zstyle -T ":vcs_info:${vcs}:${usercontext}" "enable" || {
        [[ -n ${VCS_INFO_message_0_} ]] && VCS_INFO_set --clear
        return 0
    }
    zstyle -a ":vcs_info:${vcs}:${usercontext}" "disable" disabled

    zstyle -a ":vcs_info:${vcs}:${usercontext}" "disable-patterns" dps
    for pat in ${dps} ; do
        if [[ ${PWD} == ${~pat} ]] ; then
            [[ -n ${vcs_info_msg_0_} ]] && VCS_INFO_set --clear
            return 0
        fi
    done

    VCS_INFO_maxexports

    (( found = 0 ))
    for vcs in ${VCSs} ; do
        [[ -n ${(M)disabled:#${vcs}} ]] && continue
        vcs_comm=()
        VCS_INFO_${vcs}_detect && (( found = 1 )) && break
    done

    (( found == 0 )) && {
        VCS_INFO_set --nvcs
        return 0
    }

    VCS_INFO_${vcs}_get_data || {
        VCS_INFO_set --nvcs
        return 1
    }

    VCS_INFO_set
    return 0
}