Print newline in PHP in single quotes

Question

I try to use single quotes as much as possible and I\'ve noticed that I can\'t use \\n in single quotes. I know I can just enter a newline literally by pressing return, but

Answer 1

I wonder why no one added the alternative of using the function chr():

echo 'Hello World!' . chr(10);

or, more efficient if you're going to repeat it a million times:

define('C_NewLine', chr(10));
...
echo 'Hello World!' . C_NewLine;

This avoids the silly-looking notation of concatenating a single- and double-quoted string.