Valid characters in a module name

David M. Lloyd david.lloyd at
Tue Jan 3 16:04:48 UTC 2017

On 01/01/2017 07:44 PM, Ess Kay wrote:
> Hi Rémi,
>> You can update your tool to use an escape character
> Sure. However, can you imagine how much work it would be to update a Java
> source parser to allow identifiers like package and class names to contain
> escaped semi-colons, single quotes or double quotes? My scenario and that
> of many others is the same.  It can be done but the result will be ugly.
> I repeat my earlier question, are there existing module systems out there
> that allow spaces, quotes and semi colons to appear in a module name?

Yes.  Java EE and JBoss Modules both allow this, as do systems where a 
file name is a module name.

> All I ask is that serious thought be given to how much flexibility is
> really needed in a module name.  There are signs that there has not yet
> been much serious thought.  For example backspace is not allowed but DEL
> (0x127) is allowed.

There has been plenty of serious thought, and I agree that we should be 
disallowing all Unicode controls of any kind, but my understanding is 
that there are implementation complexities involved which make this 
somehow impractical.  However UTF-8 parsing is not difficult so 
hopefully this can be revisited at some point.


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