HOWTO remove empty lines with Regex

[tor]

Hi
I wan't to remove all empty lines in a file.
How can I do that with a regex:
s/<something>//;
What is this <something>

Torfinn

 

[Anno Siegel]

Hi
I wan't to remove all empty lines in a file.
How can I do that with a regex:
s/<something>//;
What is this <something>

Apparently you want to remove empty lines not from a file, but a string.

There may be such a <something>, but it's easier with a different regex.

s/\n+/\n/g

does it.

tr/\n//s

does it faster.

Anno

 

[Tad McClellan]

I wan't to remove all empty lines in a file.

perl -n -i.old -e 'print unless /^\s+$/' file

 

[Glenn Jackman]

perl -n -i.old -e 'print unless /^\s+$/' file

Nitpick mode: remove empty lines too:
perl -n -i.old -e 'print unless /^\s*$/' file
^
^

 

[tor]

This might clearify
I got this file:
-----------------
Line 1<newlin>
Line 2<newlin>
<newlin>
Line 4<newlin>
----------------
I want this
-----------------
Line 1<newlin>
Line 2<newlin>
Line 4<newlin>
----------------

I want to remove the line who only contains <newline>,
so that the array @var only lines that contains data.

while(<FILE>) {
s/<something>/<nothing>/;
#Where <something> the regular expression I'm missing
push(@var,$_);
}

 

[Gunnar Hjalmarsson]

This might clearify
I got this file:
-----------------
Line 1<newlin>
Line 2<newlin>
<newlin>
Line 4<newlin>
----------------
I want this
-----------------
Line 1<newlin>
Line 2<newlin>
Line 4<newlin>
----------------

I want to remove the line who only contains <newline>,
so that the array @var only lines that contains data.

while(<FILE>) {
s/<something>/<nothing>/;
#Where <something> the regular expression I'm missing
push(@var,$_);
}

In that case, you are on the wrong track with that s/// operator. You
can just do:

while (<FILE>) {
push @var, $_ unless $_ eq "\n";
}

 

[Jeff 'japhy' Pinyan]

Nitpick mode: remove empty lines too:
perl -n -i.old -e 'print unless /^\s*$/' file

But \n is matched by \s, and the $ anchor doesn't HAVE to match a newline,
so on a string like "\n", both /^\s+$/ and /^\s*$/ match.