I've been asked by Jonathan M. Hollin (of the West Yorkshire Perl Mongers) to provide some nifty Perl articles for the WYPM web site, so I've gotten back into the article-writing-shindig. It's a general column (for no group in particular) called "Just Another Perl Article". The first article is "Getting a Handle on Files", and covers some filehandle tricks (and a bit of obfuscation). If you find it useful, you can go ahead and use it for whatever purpose you see fit (so long as you keep the file intact).

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Jeff[japhy]Pinyan: Perl, regex, and perl hacker.
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

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Re: Just Another Perl Article
by stefan k (Curate) on Nov 02, 2001 at 15:06 UTC
    Hi :-),
    this was a pretty cool read! I learned a lot from it. Thanks.

    One question though: I don't really get this little piece of code: 

    $\ = $/; # ORS = IRS = "\n"
$, = ":"; # OFS = ","

while (<PASSWD>) {
  chomp;  # removes $/ from $_
  my @f = split $,;  # splits $_ on occurrences of $,
  # fool around with @f
  print MOD @f;
}

    [download]
    Why would it put a newline to the end of each line during the print? You say that "$\ goes where you put a \n in your print()" but you're chomp()ing the newlines.

    What do I miss here?

    Hmm, now looking at it I get even more questionmarks on my forehead:

    1. What's the point of assigning a colon to $, when split doesn't use it by default?
    2. Why do you have to assign $\ with $/? Aren't they supposed to have the same value anyway?
    3. Why don't we have an abbrev like <c> for the code-Tag, since it is really much to type *grin*?

    Still, as I said above: good read!

    Regards... Stefan
    you begin bashing the string with a +42 regexp of confusion

    ps: a typo in your article: 

    $ARGV this holds the input source currently begin read from

    [download]
    should probably be "being read from", er?
[reply]
[d/l]
[select]
      • $/ is the input record separator. This is "\n" by default.
      • $\ is the output record separator. This is the empty string by default. Setting it to $/ means that you no longer need to put a "\n" on the end of each print statement.
      • $, is the string that is output between each element of the list passed to print. The default value is the empty string. By setting it to ":" we don't just control the split statement, but also the print statement. The elements of @f are printed separated by ":" characters.

      Does that help? You can get more info on special Perl variables like these in perlvar.

      --
      <http://www.dave.org.uk>

      "The first rule of Perl club is you don't talk about Perl club."

[reply]

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