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From: worley@compass.com (Dale Worley)
Newsgroups: comp.lang.perl
Subject: print <FILE>;
Message-ID: <1991Apr8.161504.2872@uvaarpa.Virginia.EDU>
Date: 8 Apr 91 16:15:04 GMT
Sender: mmdf@uvaarpa.Virginia.EDU (Uvaarpa Mail System)
Reply-To: worley@compass.com
Organization: The Internet
Lines: 45


   From: brossard@sic.epfl.ch (Alain Brossard EPFL-SIC/SII)

      print NEW <FILE>;

	   It not only prints the next line of FILE as
   I wanted but prints all the rest of FILE.

You've gotten bitten by the one truly non-obvious feature of Perl: You
must always be aware of array vs. scalar context.  'print' provides an
array context for its arguments.  For better or worse, not knowing the
contexts provided by all the operators one uses is as dangerous as not
knowing the difference between $foo, $foo(1), and $foo{1}.

   Anyway I suggest adding:

	   print <STDIN>;

      in the paragraph that says that all the following are equivalent:

	    while ($_ = <STDIN>) { print; }
	    while (<STDIN>) { print; }
	    for (;<STDIN>;) { print; }
	    print while $_ = <STDIN>;
	    print while <STDIN>;

Well, that paragraph is discussing flow-of-control constructions, not
array handling.

      I wanted to do print $_, <FILE>, <FILE>;  and I had to do:
   print $_ =  <FILE>; print $_ = <FILE>;
      The fact that I need to do an assignment seems counter intuitive!

You can do

	print scalar(<FILE>);

to execute <FILE> in a scalar context, i.e., reading one line.

Dale

Dale Worley		Compass, Inc.			worley@compass.com
--
I am successful because I am the only person in my city
who is not heavily addicted to powerful narcotics.