Valid characters in a module name

[Ess Kay]

> Why wouldn't Peter's syntax proposal suffice
For any syntax to work (in ANY context) you need to be able to distinguish
between the use of that syntax and the specification of an identifier (e.g.
a module, package, class, field or method name) which happens to match that
syntax.  Let's take Peter's string #"\\u0022\\\"" as an example.  How is
that string to be interpreted? Is it an example of the proposed syntax that
should be interpreted as the 11 character identifier \\u0022\\\" or is it a
14 character identifier starting with # and ending with to double quotes?
Module, package, class, field and method names can legally start with the 2
characters #" and end in a double quote.  That is why Peter's syntax would
not work.  This is the difficulty when you specify that almost any
character and character combination is a valid in an identifier.

> I thought your problem was that users needed a way to express
> "crazy identifiers" in _your_ (or other Java-like) script languages.
My discussion of  the problem of crazy identifiers in JAR manifests was
more of "parting shot". It is very easy to be ultra flexible in a
specification. It is very concise and even aesthetically pleasing.
However, it can be much, much harder to actually support that ultra
flexibility in the practice.  Problems can occur in unexpected places. Such
is life.