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

[John Rose]

On Sep 10, 2008, at 12:36 PM, Alex Buckley wrote:
> The spec RFE is here: http://bugs.sun.com/view_bug.do?bug_id=6746458
>
> There may be other ways of specifying this; comments welcome,  
> either here or on bugs.sun.com.
>
> Alex

Thanks!

One nit:  The grammar doesn't mention superquoting.  It should use  
the same rules as for char and string literals, plus the constraint  
"except /.;<>[".

I added three negative jtreg tests.  See the mlvm patch repo.:
   http://hg.openjdk.java.net/mlvm/mlvm/langtools/file/tip/quid.patch

(I tested the negative tests by disabling each of the three tested  
constraints, and verifying that each negative test unexpectedly  
passed in turn.)

I also added customized error messages.

-- John