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Postings from August 2008
In-Reply-To: Message from jvromans@squirrel.nl (Johan Vromans)
of "Fri, 01 Aug 2008 12:28:49 +0200." <18578.58721.180685.719191@phoenix.squirrel.nl>
> [Quoting Tom Christiansen, on July 31 2008, 16:15, in "Fighting the Good Fi"]
>> In-Reply-To: Message from Johan Vromans <jvromans@squirrel.nl>
>>> I'd go for a nice iterator class instead of <<<<>>>> weirdness.
>> But now I'm curious--a condition for which, per Dorothy Parker, there
>> is no cure :). Still, I'll try to cure it by asking whether you
>> might you mean:
>> (1) A class that has some sort of:
>>
>> use overload "<>" => sub { ... };
> Basically, yes.
Good!
> =head1 NAME
> Iterator::Diamond - Iterate through the files from ARGV
> =head1 VERSION
(and so and so forth)
Gosh, Johan, you're ahead of the game! With the doc/spec all complete and
written out nicely like that, that makes it what, like 90% done? (and only
90% to go, I know, I know. :-)
Does it iterate per glob, too? ;-}
I really need to break myself from using
open(SETUP, <~joeblow/.exrc>)
at least, or maybe even also
# DON'T NEED: chdir <~joeblow> || grump();
while ($dot_his = <~joeblow/.??*>) { # CUZ gets full pathname
next unless -f -r -T $dot_his; # no, no -A :-)
open(SETUP, "< $dot_his\0") || grump();
...
}
but it's just so danged convenient. The problem was that last I looked,
you have to finish the iteration yourself (as in example #2 with the
while), or else there'll be a dangling dirhandle left unclosed and
consuming system resources: one of your process's FDs--and also thus
one out of the syswide UFD table in the kernel, too.
I know: old perl hackers, like old nuns, have strange old habits.
I do think (but don't quote me; quote him if you can) that Larry
likes the angle-operator (as he calls it) to be an iterator, or
rather *the* iterator, and that classes that co-opt it for their
own iteration strategies are cool. That makes your idea cool.
I still yearn for <> to work on DHs opened by opendir, too.
Never saw why it didn't.
$his_dir = <~joeblow>; # XXX: just lost an FD
opendir(DH, $his_dir) || grump();
### chdir($his_dir) || grump();
### "I hate programs that chdir" --Boyd Roberts
while (<DH>) {
next unless /^\./;
next unless -f -r -T; # WRONG: now needs $his_dir!
open(SETUP, "< $his_dir/$_\0") || grump();
....
}
--tom