Syntax for union types

zwetan zwetan at
Fri Nov 9 08:53:45 PST 2007

On Nov 9, 2007 5:13 PM, Lars Hansen <lhansen at> wrote:
> > the option to have sealed package would be indeed an
> > interesting feature in ES4, is this is discussed somewhere in
> > the wiki ?
> Not to my knowledge, and we've in any case not incorporated anything
> like this.

ok I thougth that what you mentioned was already discussed by TG1.

> A couple of obvious solutions would be to have package fragments
> designated "final" be the only package fragment for the package, or to
> have a "final"-designated package fragment provide the last fragment of
> the package, preventing the loading of subsequent fragments.
> Whether this is a good idea or not depends in part on whether you think
> packages and namespaces are for secrecy/integrity, as implied by the use
> of eg "private" in a class ("private" is just a namespace), or if
> namespaces are just for collision avoidance.

well it depends on the context, for security it could be good to have
final package, if I remember well inside the spec there were a namespace exemple
showing how to "secure" the access to a class using namespaces,
but apparently we don't have access to the spec pages anymore (?).


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