in reply to Is there a better way to check if an array is empty?

I want this for loop to get executed only when @array has elements.
Then no check is needed. 
foreach my $base_p4path (@array) {
    # Execute once for each element in @array.
    # Hence *NO* loop iteration if @array is empty.
}

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Re^2: Is there a better way to check if an array is empty?
by iphone (Beadle) on Dec 21, 2010 at 19:08 UTC

    I should have been more specific.Basically I want to push $newfile to another array @newfiles only if the array is empty and the instructions after the push instruction should not be executed.The following works for me but I want to know if there is a better way 

    if{
            my $newfile="$file\n";
                        @array = grep(/\Q$newfile\E/,keys %hash);
            if (!@array)
            {
             push @newfiles,$newfile;
             #last;
            }
            next unless (@array);
                      .....................
}

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[reply]
[d/l]
      You are using next, and have an outcommented last, without a loop. You also have an if followed by a block.

      I can't make sense of what you are doing, let alone suggest a better way. I do know that many people prefer to use a consistent indenting, but for some reason, many people asking the questions on Perlmonks seem to prefer some random indentation. (But I've seen worse).

[reply]

        To say in short again,I am searching for a new file in the keys of a hash and pushing the grep results to an array,if the array is emtpy then only push the new file to another array "@newfiles" and then come out of the loop(that's the reason I added a next)

[reply]
      This "code" is gobbledygook. @array is not needed. Grep in a scalar context returns the number of matches. 
      my @files = (.....some file names...);
my %hash = (....keyed upon file names...);
my @newfiles;

foreach my $file (@files)
{
   push (@newfiles, $file) unless ( grep{/\Q$file\E/}keys %hash );

   # pushes the name of $file to @newfiles if no match
   # is found to the pattern within keys of %hash.
}

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[d/l]

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