Re: I still can't get only the necessary lines from the file.

in your text file example you have Start context and * Exit context *
in your code you're matching for START context and End context
I modified the code to match correct, tested, and works fine:
will print everything except what your matching for in the print unless

open (DATA,"<c://xxx.txt") || die "Can't open xxx.txt: $!\n";
while(<DATA>) {
    if (/Start context/ .. /\* End Context \*/)  {
         print unless /(Start context|\* Exit context \*)/;
     }
}
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Comment on Re: I still can't get only the necessary lines from the file. Download Code

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Re^2: I still can't get only the necessary lines from the file. by sashac88 (Beadle) on Jul 01, 2004 at 07:19 UTC
Oops -my mistake.I have the correct line in my code's unless. \* Exit context \* The problem is that in print results I get lines that are not between the closest "Start context" and "* end context ". I suspect that maybe the problem is in this line: if (/Start context/ .. /\ End Context \/) which IMHO takes all the lines between the first "Start context" in the file and last " end context " . Am I right? Or the line: if (/Start context/ .. /\ End Context \/) looks for the closest "Start context" and " End context *" Thanks	[reply]
Re^3: I still can't get only the necessary lines from the file. by gaal (Parson) on Jul 01, 2004 at 10:00 UTC
The `..` "flip-flop" operator (see perlop) is true "between" the two operands. That is, once the left-hand match is true, the flip-flop is true, until whenever the right-hand match succeeds. Then it's false until the left-hand match is true, and so on. So, no: `if (/Start context/ .. /\* End Context \/) {` doesn't "take" "all the lines between the first 'Start context' in the file and last ' end context *'", but indeed only those within any of the contexts (and the start marker too, but not the end marker).	[reply] [d/l] [select]