Regex to remove data

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Regex to remove data by Athanasius (Archbishop) on Nov 06, 2012 at 14:13 UTC
Something like this should do the trick: `#! perl use strict; use warnings; my @lines = <DATA>; s/ ^ [A-Z\s]+ $ //x for @lines; print for @lines; __DATA__ AAAAAAAA AAAA AAAAAAA AAAA AAA AAA Leave me intact PLEASE` [download] Output: `0:10 >perl 369_SoPW.pl Leave me intact PLEASE 0:13 >` [download] Update 1: Note that this will also remove blank (i.e. empty) lines. Update 2: Changed `print "@lines";` [download] to `print for @lines;` [download] to address the issue of leading spaces raised by Anonymous Monk, below. Hope that helps, Athanasius <°(((>< contra mundum	[reply] [d/l] [select]
Re^2: Regex to remove data by rjt (Curate) on Nov 06, 2012 at 17:19 UTC
This is good, but the OP did say he wanted to remove the lines from a "large file", but your approach reads the entire file into an in-memory array (`@lines`) and processes that. Check out my reply below for an example that loads only one line into memory at a time (the `-n` switch assumes `while (<>)`).	[reply] [d/l] [select]
Re^2: Regex to remove data by Anonymous Monk on Nov 06, 2012 at 14:23 UTC
Thanks,though it adds a leading space to each line	[reply]
Re: Regex to remove data by locked_user sundialsvc4 (Abbot) on Nov 06, 2012 at 14:37 UTC
Also, don’t overlook the obvious `grep` (or `egrep`) commands, if you have them on your system . . . You might not have to “write a program” to do this at all. Simply use the `-v` option to output all lines which don’t match the pattern.
Re: Regex to remove data by rjt (Curate) on Nov 06, 2012 at 17:10 UTC
It looks like you want to remove lines that (optionally) contain spaces in addition to uppercase. This one-liner will do the trick: `perl -ne 'print unless /^[A-Z\s]+$/' <in.txt >out.txt` Of course if you are including this in a larger Perl program, you can just nab the regex out of that, and use it in a loop construct of some kind. For example: `while (<>) { print if !/^[A-Z\s]+$/ }`	[reply] [d/l] [select]
Re: Regex to remove data by space_monk (Chaplain) on Nov 06, 2012 at 17:10 UTC
`perl -pe 's/ ^ [A-Z\s]+ $ //x' <your_data`, anybody?	[reply] [d/l]
Re: Regex to remove data by trizen (Hermit) on Nov 07, 2012 at 07:55 UTC
Keeps the lines that are empty or that contain only whitespace characters: `perl -ne 'print if not /[A-Z]/ && /^[A-Z\s]+$/' file.txt`	[reply] [d/l]