[patch] 6746458 support for exotic identifiers (identifier superquote)

[Per Bothner]

John Rose wrote:
> The proposed use of # does not affect any other proposal on the table.  
> The # has to be immediately followed by a double-quote character (and a 
> valid string literal) in order to constitute a quoted identifier.  Given 
> the small number of ASCII characters, it is unreasonable to ask that 
> potential language extensions have exclusive rights to any of them.

Yes, we don't want to grab any single ASCII characters - instead
we're grabbing a sequence of two ASCII characters: '#' '"'.
Using '"' as the second of those is convenient, because it makes
it obvious that string escapes are allowed - but we can allow
string escapes even if we use another delimiter.

As an old Lisper/Schemer, something like this
   \|class|
looks more natural.  You'd still allow string escape sequences -
to generate "|\n|" you could write:
   \|\|\n\||
Ugly, but that's an extreme example, of course.
-- 
	--Per Bothner
per.bothner at sun.com   per at bothner.com   http://per.bothner.com/