Re: variable declaration

From: Michael Tobis (mt_at_3planes.com)
Date: 01/31/05 

Date: 31 Jan 2005 08:19:19 -0800

With all due respect, I think "so go away if you don't like it" is
excessive, and "so go away if you don't like it and you obviously don't
like it so definitely go away" is more so. The writer is obviously
neither a native speaker of English nor an accomplished user of Python,
so there are two language issues here. Try expressing your reply in
Russian before deciding that "very ugly" means exactly what you think
it does. I think just saying that "experienced Python users have not
found the lack of declarations to be a major hindrance" would have been
more appropriate.

Also, the assertion that "Python has no declarations whatsoever" is no
longer obviously true. In the 2.4 decorator syntax, a decorator line is
not executable, but rather a modifier to a subsequent symbol binding. I
call it a declaration. I found this disappointing in that it seems to
me a violation of "Special cases aren't special enough to break the
rules" but on further reflection it enables consideration of what a
whole slew of declarative constructs could achieve.

To begin with, now that the design constraint of "no declarations" has
been shown to be less than absolute, why not allow for perl-style ('use
strict') declarations? It actually is very useful in the small-script
space (up to a few hundred lines) where the best Perl codes live.

Let me add that I remain unconvinced that a language cannot combine the
best features of Python with very high performance, which is ultimately
what I want. It seems to me that such a language (possibly Python,
possibly a Python fork, possibly something else) will need substantial
programmer control over references as well as referents.

It seems to me that Python has a weaker case for purity in this regard
now that the dam has been breached with decorator syntax, which is, I
think, a declaration.

Let me conclude with the confession that I'm still on the steep part of
the learning curve (if it ever flattens out at all...). Python has
definitely significantly modified how I think about things, and I
deeply appreciate all the efforts of you veterans. So I say this all
with some trepidation, because I don't want to join Alexander in
inadvertently offending you. And since I presumably missed some intense
flame wars about decorators by only a couple of months, this may be a
real hornet's nest I am poking.

In summary, again with all due respect and gratitude for the
spectacularly excellent product that Python is today, I wonder *why*
this strong aversion to declarative statements, and *whether* decorator
syntax constitutes a violation of it. I'd appreciate any responses or
links. 

--
mt

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