comment on

And in today's "making Perl work a lot harder than you need to do", let's nominate the following entry:

my $ticker=['http://perlmonks.org/index.pl?node_id=30175&xmlstyle=rss'
+,
            "http://rss.news.yahoo.com/rss/science"]->[rand 2];
[download]

So, we've asked Perl to construct an array, take a reference to it, then dereference that reference to pick out one of the items, then discard the reference, which then garbage-collects the array. All when we could have written that this way:

my $ticker=('http://perlmonks.org/index.pl?node_id=30175&xmlstyle=rss'
+,
            "http://rss.news.yahoo.com/rss/science")[rand 2];
[download]

saving two characters of typing, and all that mess of creating the new array and reference and garbage collecting. We're simply constructing a list, then picking out an element of that list with a literal slice (a construct I suggested for Perl 3, by the way {grin}).

To optimize this further, I'd go with a qw for that first list:

my $ticker=(qw(http://perlmonks.org/index.pl?node_id=30175&xmlstyle=rs
+s
            http://rss.news.yahoo.com/rss/science))[rand 2];
[download]

And in recent versions of Perl, you can even drop that outer set of parens:

my $ticker=qw(http://perlmonks.org/index.pl?node_id=30175&xmlstyle=rss
            http://rss.news.yahoo.com/rss/science)[rand 2];
[download]

I saw bracket-arrow-bracket as a "cute syntax" once. I'm trying to stomp it out, because there's an equivalent construct (as I showed) that is a lot less work for Perl. Please don't propogate "cute syntax" that is more expensive.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to •Re^2: Writing a simple RSS feed 'grabber' with XML::Parser. by merlyn
in thread Writing a simple RSS feed 'grabber' with XML::Parser. by DigitalKitty

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