Is there any way of saying "at each change in"? i am reading down a column in a text file, and i want to do something at each change. so if i have 
apples
apples
apples
oranges

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i want to "do something" on the first apple, and on the first orange. do i need to use a counter, or say "if $foo ne $previousfoo", or is there any easier way? the search didn't come up with anything. thanks.

In reply to At each change in... by malaga

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