From: Rob Dixon <[EMAIL PROTECTED]>
> Jenda Krynicky wrote:
> > From: "Dr.Ruud" <[EMAIL PROTECTED]>
> >> "Jenda Krynicky" schreef:
> >>> Rob Dixon:
> >>>>
> >>>> local $" = ',';
> >>>> print "@array\n";
> >>>
> >>> print join(',', @array), "\n";
> >>>
> >> is much cleaner and safer. Leave $" alone.
> >> I don't agree. It is totally fine to use a local-ed $", if it is inside
> >> a minimal block.
> >
> > Is it? What if the array you're gonna print is tie()d? Maybe it is
> > not now, but what if it becomes later? To share the array between
> > threads/processes, to store it on disk, to ...
> >
> > If there was no simple and clear way to print the array with a
> > specific delimiter, I'd say go ahead. But there is. A way that's much
> > easier to understand. Without having to know about an obscure builtin
> > variable that affects the way arrays are interpolated into strings.
>
> A program with arrays that are tied in one place and not in another has bigger
> problems than this anyway.
I'm not talking about the program having one array tied and not tied
in various places. I'm talking about a program that evolves so that
an array that wasn't tied in the first version, is tied in a later
one. Because it grew too big to fit in memory, because you started
using several threads/processes, because ....
> But I don't see a problem with using $" with tied
> arrays, unless the tied class happens to overload stringification.
Nope. Unless the tied class interpolates an array into a string
expecting to get the elements separated by spaces somewhere in the
methods invoked by reading the whole array. Or any of the functions
used in the methods does.
> print join(',', @array), "\n";
>
> is a lot noisier and IMO clumsier than
>
> {
> local $" = ',';
> print "@array\n";
> }
>
> and after all, even if you don't know what $" does it's very simple to look it
> up and also easy to remember.
>
> Rob
31 characters with no special variables vs. at least 42 chars with
one special variable affecting another statement?
"Print the @array joined by commas and a newline." vs "Start a block.
In this block the items of any array interpolated into a string are
to be separated by commas. Now print the @array interpolated into a
string (viz above) followed by a newline. And now please forget we
changed the way arrays are interpolated in string."
Sure you can look up $", but why? The join() is clear without looking
anything up.
And assuming Perl 5.10 we might even be comparing
say join(',', @array);
vs
{
local $" = ',';
say "@array";
}
I wonder how long would it take before someone decides that the
quotes are not needed and changes that to
{
local $" = ',';
say @array;
}
Jenda
===== [EMAIL PROTECTED] === http://Jenda.Krynicky.cz =====
When it comes to wine, women and song, wizards are allowed
to get drunk and croon as much as they like.
-- Terry Pratchett in Sourcery
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