Re: How to print the lines immediately above and below a matching line?

if ($this_line =~ /<DATA>/) {

Are you trying to read from the special DATA handle, or are you trying to match the exact string <DATA>? re indicates you are doing the latter:

perl -Mre=debug mycode.pl
Compiling REx "<DATA>"
Final program:
   1: EXACT <<DATA>> (4)
   4: END (0)
anchored "<DATA>" at 0 (checking anchored isall) minlen 6 
Error opening file - No such file or directory
Freeing REx: "<DATA>"
[download]

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Re^2: How to print the lines immediately above and below a matching line? by Bio90 (Initiate) on Nov 25, 2012 at 13:36 UTC
Hi, thanks for your reply. I am trying to match from the `DATA` handle.	[reply] [d/l]
Re^3: How to print the lines immediately above and below a matching line? by toolic (Bishop) on Nov 25, 2012 at 13:41 UTC
Then you need to change your code. Something like: `my $data = <DATA>; chomp $data; if ($this_line =~ /\Q$data/)` [download]	[reply] [d/l]
Re^4: How to print the lines immediately above and below a matching line? by Bio90 (Initiate) on Nov 25, 2012 at 13:55 UTC
I have tried that but it has returned a `"Use of uninitialised value $data".` I do not understand - surely `$data` is initialised by `my $data = <DATA>;`?	[reply] [d/l] [select]
Re^5: How to print the lines immediately above and below a matching line? by Anonymous Monk on Nov 25, 2012 at 14:00 UTC
Re^6: How to print the lines immediately above and below a matching line? by Bio90 (Initiate) on Nov 25, 2012 at 14:09 UTC
Some notes below your chosen depth have not been shown here
Re^3: How to print the lines immediately above and below a matching line? by Anonymous Monk on Nov 25, 2012 at 13:40 UTC
Maybe you should read a line from that handle instead ... don't skip the basics, read perlintro	[reply]
Re^4: How to print the lines immediately above and below a matching line? by Bio90 (Initiate) on Nov 25, 2012 at 13:52 UTC
I'm sorry, I am a Biology student and I have merely had perl suggested to me as a means to an end in order to get my data into a usable format.	[reply]
Re^5: How to print the lines immediately above and below a matching line? by Anonymous Monk on Nov 25, 2012 at 14:01 UTC