No valid literal format for unprintable Strings

[blairmcg]

Smalltalk doesn't have an escaped literal form for characters that don't have a standard glyph, e.g. whitespace, null, escape. Most languages provide an escaping mechanism to allow these to be specified as literals using an alternate form, e.g. '\n' for '\x0D' for linefeed. This c-style escaping has been adopted into many languages, and although it doesn't use the traditional Smalltalk form for expressing hex, it is much more concise and generally understood.
The ability to specify characters with arbitrary code points will become even more important when Unicode is supported.

[blairmcg]

Done for Characters