function _prompt_virtualfish -d "Display activated virtual environment (only for virtualfish, virtualenv's activate.fish changes prompt by itself)"
[ "$theme_display_virtualenv" = 'no' -o -z "$VIRTUAL_ENV" ]; and echo -n -s '--'; and return
echo -n -s (basename "$VIRTUAL_ENV")
function _prompt_virtualfish -a sep_color -a venv_color -d "Display activated virtual environment (only for virtualfish, virtualenv's activate.fish changes prompt by itself)"
[ "$theme_display_virtualenv" = 'no' -o -z "$VIRTUAL_ENV" ]; and return