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Re^5: Foreach Loopsby Roy Johnson (Monsignor) |
on Mar 16, 2005 at 13:57 UTC ( [id://439944]=note: print w/replies, xml ) | Need Help?? |
I'm glad you got a kick out it, but I really have to discourage you from using it for indexing. Can you imagine explaining it?
"What the hell is this mess?"The most common use of a flip-flop is to extract a range of lines from a file. You set the left side to match the start of the range, and the right side to match the end of the range. If either operand is a constant expression, it is implicitly compared to $. (the line number). That is what kept me from using a simple expression like (1==1)..(1==0). Actually, now that I think about it, the expressions I used ought to be constant expressions. Anyway, I did think of a couple interesting alternatives for always-true flip-flops. Note that in the former, I have to use the 3-dot version, so that both operands aren't evaluated on the same pass. $index starts out zero, so the left side is true. After that, it's non-zero, so the right side is false. The second example just incorporates a variable into an expression whose truth is constant. I used $. because of its association with the operator, but any variable would do. Caution: Contents may have been coded under pressure.
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