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Postings from September 2009
On Sunday 13 September 2009 02:43:52 Jenda Krynicky wrote:
> From: Shlomi Fish <shlomif@iglu.org.il>
>
> > > use FileHandle;
> > > my $signature = new FileHandle;
> > > $signature->open("<$signature_file")or die "Could not open
> > > file\n";
> >
> > You should use IO::Handle instead of File::Handle (or IO::File in your
> > case), and use the three args open. It's nice you've used die.
>
> Nope. You should not be bothering with thatever class is at the
> moment behind the Perl filehandles and just use open() as a function.
> Not everything has to be an object
>
> open my $SIGNATURE, '<', $signature_file
> or die "Could not open '$signature_file': $^E\n";
>
Indeed. No need to call "$SIGNATURE" with all-caps. "$signature_fh" is good
enough. I should note that if you do "use IO::Handle;" at the top, then you
can all methods on $signature_fh.
> > $signature is not a good name for a filehandle - better call it
> > $signature_fh.
>
> I use all capitals for filehandles. Both oldstyle and lexical.
I dislike all-capitals because it's like shouting and are harder to read. But
this is a colour of the bike-shed argument:
http://bikeshed.com/
>
> > > my $fileHandle = $_[0];
> >
> > Accessing $_[$idx] is not very robust - you should do:
> >
> > <<<
> > my $fileHandle = shift;
> >
> >
> > Or:
> >
> > <<<
> > my ($fileHandle) = @_;
>
> Nope. Accessing $_[$idx] all over the place within the subroutine
> would be prone to errors and inconvenient (though sometimes
> necessary), what syntax do you use to copy the parameters into
> lexical variables is largely unimportant. And sometimes you can't
> just shift() off parameters from @_, you need to keep them there.
>
Generally, I sometimes use something like:
sub my_method
{
my $self = shift;
my ($param1, $param2, $param3) = @_;
.
.
.
if (COND())
{
return $self->other_method(@_);
}
}
Normally I don't like using $_[0], $_[1], etc. directly. The only use I can
think for them is to modify them in place using aliases. But in this case it
is better and safer to pass them as references.
> > > my $customer_msg_html = $customer_msgStart_html . OrderFromForm_html()
> > > . $customer_msgEnd_html . $scalar_sig;
> >
> > Your style is inconsistent between camelCase, and
> > underscore_separated_identifiers.
>
> Maybe there is a meaning to the underscores on some places and case
> change in others. Don't be so quick. The fact that you do not see a
> pattern from a very short example doesn't necessarily mean there
> isn't one. It may very well be too big to fit in the small cut hole
> that you see.
>
Maybe. It's still hard to read.
Regards,
Shlomi Fish
> Jenda
> ===== Jenda@Krynicky.cz === 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
>
--
-----------------------------------------------------------------
Shlomi Fish http://www.shlomifish.org/
Freecell Solver - http://fc-solve.berlios.de/
Chuck Norris read the entire English Wikipedia in 24 hours. Twice.
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