Re: controlled type in generic package?

[Jon S Anthony <jsa@synquiry.com>]

Nick Roberts wrote:
> 
> "Florian Weimer" <fw@deneb.enyo.de> wrote in message
> news:871yt8rvhq.fsf@deneb.enyo.de...
> > ...
> > Python permits class declarations anywhere a statement is allowed (in
> > fact, a class declaration *is* a statement).  Python classes are
> > usually used to implement closures:
> > ...
> > Python is not a flat language at all.
>
> Python is an interpreted language, and whilst classes can apparently
> be declared within nested blocks, they all effectively exist at the
> same level _within the interpreter_. In this sense, Python is a
> 'flat' language. A compiled language cannot handle things in this
> way. Similar comments apply to the LISP family and others.

To the extent this says anything it is plainly rubbish.  "Exist at the
same level within the interpreter" has no sense.  Presumably you are
trying to say that there are no "packages" for large scale lexical
scoping.  However, this is incorrect.  Python does have packages,
though no nested scoping (in a package/module it's either global or
outer function scope - which is why you it does _NOT_ have closures).
OTOH, the class hierarchy is just that - a hierarchy (as in "not
flat").  Python definitely sucks, but not for any "flatness" reasons.

Beyond this, whether the language is compiled or not is also
irrelevant. For example, Common Lisp implementations are typically
compiled (to machine code and are _extremely_ efficient).  Common Lisp
has a multiply nesting hierarchical package structure which is also
dynamic (you can change package structure, importations, shadowing,
etc. at runtime, though this is typically _not_ something you would
do).


/Jon

-- 
Jon Anthony
Synquiry Technologies, Ltd. Belmont, MA 02478, 617.484.3383
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 Who'd notice?"  -- Londo Mollari