Assuming you don't want to write the three lines which compare the present value to some old value, you could use: 

while(<DATA>) {

  chomp;
  print "pleasure - $_\n" if ($_ ne $old) && ($old = $_);
}

__DATA__
apples
apples
apples
oranges
pears
bread
bread

[download]

--
Steve Marvell

In reply to Re: At each change in... by marvell
in thread At each change in... by malaga

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