I'm not sure if the title is any good but I can't think of a better description.

I have a bit of code that parses a file and does something for a block of lines in the middle. This is a good candidate for the flip-flop operator and I coded my loop like this: 

foreach (grep /start/ .. /stop/, @data){
  # do_stuff
}

[download]
Which is fine, but then I noticed it is not supposed to do_stuff on the boundaries. My question is: is there a better way of doing this than: 
foreach (grep /start/ .. /stop/, @data){
  next if /start/;
  last if /stop/;

  # do stuff
}

[download]
The regexes are a lot more involved in real life. I don't like the idea of copying chunks of code either.

I tried using the sequence counter, but it was not visible outside the grep...can anyone explain this too?

-- iakobski

In reply to flip-flop operator and sequence number by iakobski

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