[racket] Subindex and some Latex code withing Slideshow

At Mon, 7 Jul 2014 17:55:55 -0500, David Merinos wrote:
> Is there a way to display things such as $G_f$ would display in Latex but
> using Slideshow?

Underscore handling is built into the `code` form,

 #lang slideshow
 (require slideshow/code)
 (slide (code G_f))

but for more general subscripting, use `text` with the 'subscript
style:

 #lang slideshow
 (slide (hbl-append
         (text "G" (current-main-font) (current-font-size))
         (text "f" `(subscript . ,(current-main-font)) (current-font-size))))