in reply to foreach question

Good question. foreach my $line(<INFILE>){} reads the entire file into an anonymous array, aliasing each element in turn to $line. while (my $line = <INFILE>){} reads the file one line at a time, storing each in turn in $line.

The foreach version must allocate more memory than the while loop, which is a bit slower. The tradeoff is up to you.

Update: ++chromatic points out that foreach iterates over a list, not an anonymous array.

After Compline,
Zaxo

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Re: Re: foreach question
by glwtta (Hermit) on Feb 25, 2003 at 02:56 UTC
    Thanks, I suspected as much, but wanted to make sure. In the code, the loop actually just appends $line to a string, so I suspect the effect of the foreach is not what the author had in mind.
[reply]
[d/l]
      That's what people call a 'slurp'. There's many ways to do it and if you search PerlMonks for 'slurp' you'll find them. Here's one I cooked up earlier: 
      # FILE is already open ...
{
   local $/ = undef;
   $slurp = <FILE>;
}

      [download]
      Much better (and faster) than using joins, or loops to append. Keep it inside the {} block so that the change to $/ is only temporary. (also see $/ at perldoc). The file's entire content ends up in $slurp.
[reply]
[d/l]

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