[Python-Dev] Re: Decorators: vertical bar syntax
fperez528 at yahoo.com
Mon Aug 9 19:33:59 CEST 2004
Paul Moore wrote:
> Fernando Perez <fperez528 at yahoo.com> writes:
> But we have a couple of inconsistencies to backtrack and resolve. (And
> the accepts/returns stuff is also inconsistent, but I'll stop picking
> holes in what is clearly just an example...)
> I'm not saying that the same issues mightn't exist with the
> decorator-before-def form, but I don't think the mental model for the
> decorator-after-def form is quite as clean as you'd like either...
Well, I'm not so naive as to think that there is a silver bullet here or a
perfect syntax. Obviously in all cases the programmer will need to keep some
context in his head. But this is true always:
x = 1
... many lines of code which can't change x in any way
x.append('foo') # BUG!
You spot something like this because you have a notion of local context, and
you remember that x, being an integer which hasn't changed, can't be appended
to as a list.
In fact, I'd argue that one of (not the only one) the key qualities of a good
programmer is the ability to maintain a fair amount of local and global
context in his head. This is what allows you to realize the implications of a
code change, see the potential for fruitful refactorings, etc.
But that doesn't mean that one syntax choice can't make that process _easier_.
It doesn't remove the need for having one's brain turned on, it is not a
silver bullet, but it enhances the flow of processing this kind of information
into an organized structure.
> It's still subjective :-)
I disagree, and I think I've given detailed arguments trying _precisely_ to
cast this discussion in terms which are potentially more productive than 'its
all subjective', which lead to endless running in circles. I very much
appreciate a discussion of the merits of my ideas, but hopefully in terms
which allow something which goes beyond "your shirt is blue, and I don't like
blue". I've tried to reply here in such a vein, hoping to produce useful
arguments for Guido and those ultimately making the decisions.
Yes, there is always a degree of subjectivity in all choices, and in that sense
I immensely trust Guido's intuition, ability and sense of aesthetics. But
one's subjectivity works best when assisted by other arguments as well.
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