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lists in perl

Discussion in 'Perl' started by eanair, Dec 12, 2006.

  1. eanair

    eanair New Member

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    Is the correct syntax to check if a list is empty in perl:

    if(@list == 0)

    thanks
     
  2. pradeep

    pradeep Team Leader

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    If that doesn't work, use this

    Code:
    if(scalar(@list) == 0)
    {
      #empty
    }
    
     
  3. thillai_selvan

    thillai_selvan New Member

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    You can use the following way also.
    Code:
    my @arr ;
    if ( @arr )
    {
        print "Array not empty\n";
    }
    else
    {
        print "Array empty\n";
    }
    
    There is no need to use the scalar function.
    By default this will be treated as scalar context
     
  4. thillai_selvan

    thillai_selvan New Member

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    Another way to test whether a list is empty is as follows

    Code:
    
    my @arr ;
    if ( $#arr== -1 )
    {
        print "Array not empty\n";
    }
    else
    {
        print "Array empty\n";
    }
    
    $# will contain the index value of a list.
    If a list is not having any value means this will be -1.
    If a list is having only one element means this will be 0 and so on.
     
  5. pradeep

    pradeep Team Leader

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    Code:
    unless(@arr)
    {
      ## empty
    }
    
     

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