[racket] Changing at-expressions to other-glyph-expressions

Can you use the escaping syntax that Scribble provides?  Here's an example:

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
#lang scribble/base
@list|{ this is an example with @ signs in it.  I can still
       use @ by using it like this: |@tt{Hello world}, right?}|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

It's documented in:

    http://docs.racket-lang.org/scribble/reader.html#(part._.The_.Scribble_.Syntax_at_a_.Glance)

starting around the paragraph: "In some cases, a text contains many
literal @s..."