line

Discard all but the first line of the body text. The first line ends with one of the following:

A line feed ("\n").
A carriage returm, line feed sequence ("\r\n").
The end of the text.

Anything after this is discarded.

This filter does not treat an ASCII NUL ("\0") character as a line ending, nor does it recognise a carriage return ("\r") that is not immediately followed with a line feed ("\n"). If you want to strip everything after an ASCII NUL or ASCII CR, then use the "oneline" filter instead.

Example

[filter line]Line 1
Line 2
Line 3
[/filter]

Results in:

Line 1

Source code

sub {
my $val = shift;

$val =~ s/^(.*?)\r?\n.*$/$1/s;
return $val;
}