function deactivate
    set -gx PATH $_OLD_D_PATH
    set -gx LIBRARY_PATH $_OLD_D_LIBRARY_PATH
    set -gx LD_LIBRARY_PATH $_OLD_D_LD_LIBRARY_PATH

    functions -e fish_prompt
    functions -c _old_d_fish_prompt fish_prompt
    functions -e _old_d_fish_prompt

    set -e _OLD_D_PATH
    set -e _OLD_D_LIBRARY_PATH
    set -e _OLD_D_LD_LIBRARY_PATH
    set -e DMD
    set -e DC
    functions -e deactivate
end

set -g _OLD_D_PATH $PATH
set -g _OLD_D_LIBRARY_PATH $LIBRARY_PATH
set -g _OLD_D_LD_LIBRARY_PATH $LD_LIBRARY_PATH
set -g _OLD_D_PS1 $PS1

set -gx PATH "/root/dlang/dub" "/root/dlang/dmd-2.073.2/freebsd/bin64" $PATH
set -gx LIBRARY_PATH "/root/dlang/dmd-2.073.2/freebsd/lib64" $LIBRARY_PATH
set -gx LD_LIBRARY_PATH "/root/dlang/dmd-2.073.2/freebsd/lib64" $LD_LIBRARY_PATH
set -gx DMD dmd
set -gx DC dmd
functions -c fish_prompt _old_d_fish_prompt
function fish_prompt
    printf '(dmd-2.073.2)%s' (_old_d_fish_prompt)
end