Jade: declare a variable over multiple lines

I have a jade variable declared like this:

BUTTONS = { more_blue: {caption: BUTTONS_CAPTIONS.more, style: BUTTONS_STYLES.blue}, more_red: {caption: BUTTONS_CAPTIONS.more, style: BUTTONS_STYLES.red}, see: {caption: BUTTONS_CAPTIONS.see, style: BUTTON_STYLE_PHOTOS}, see_photos: {caption: BUTTONS_CAPTIONS.see_photos, style: BUTTON_STYLE_PHOTOS}, program : {caption: BUTTONS_CAPTIONS.program, style: BUTTON_STYLE_PROGRAM}, see_program : {caption: BUTTONS_CAPTIONS.see_program, style: BUTTON_STYLE_PROGRAM} }

but I would like it to be more readable like this:

BUTTONS = { more_blue: {caption: BUTTONS_CAPTIONS.more, style: BUTTONS_STYLES.blue}
        , more_red: {caption: BUTTONS_CAPTIONS.more, style: BUTTONS_STYLES.red}
        , see: {caption: BUTTONS_CAPTIONS.see, style: BUTTON_STYLE_PHOTOS}
        , see_photos: {caption: BUTTONS_CAPTIONS.see_photos, style: BUTTON_STYLE_PHOTOS}
        , program : {caption: BUTTONS_CAPTIONS.program, style: BUTTON_STYLE_PROGRAM}
        , see_program : {caption: BUTTONS_CAPTIONS.see_program, style: BUTTON_STYLE_PROGRAM}
    }

but this code doesn't compile even if I add backslashes at the end of each line. Are there any workarounds?