Re: TRIM in Perl?

I have a problem with that one:

#!/usr/bin/env perl
use strict;
use warnings;

my @strings = ('  Test ', 'Test 2 ', ' A
', 'multi

line
string
','


');
foreach my $string (@strings) {
        $string =~ s/^\s+//m;
        $string =~ s/\s+$//m;
        print "'$string'\n";
}
[download]

Returns:

'Test'
'Test 2'
'A'
'multi
line
string'
''
[download]

That is almost correct, but it does remove a line break in the middle of the string it shouldn't: There should be two line breaks between "multi" and "line" but only one remains.

Comment on Re: TRIM in Perl? Select or Download Code

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Re^2: TRIM in Perl? by Corion (Patriarch) on Jan 12, 2011 at 10:43 UTC
Why do you add `/m` to your regular expressions? See perlop - `/m` changes the meaning of `$` and `^`.	[reply] [d/l] [select]
Re^2: TRIM in Perl? by Anonymous Monk on Jan 12, 2011 at 10:42 UTC
That is almost correct, but it does remove a line break in the middle of the string it shouldn't Who says it shouldn't? The OP wanted whitespaces removed, that is what \s means, whitespaces (\n, \r, \t, \f, and " ") Read more... (2 kB) New questions go in Seekers of Perl Wisdom (see Where should I post X?) , don't worry, yours will be moved there shortly	[reply] [d/l]
Re^2: TRIM in Perl? by Anonymous Monk on Feb 10, 2011 at 10:01 UTC
I wanted the same thing I think - remove leading and trailing space, on a per line basis, ignoring newlines. I've just done this and it seems to work, i.e. linecount remains same before and after. `cat test.dat \| perl -n -e 'chomp; s/^\s+//; s/\s+$//; print "$_\n";'` [download]	[reply] [d/l]