Returns the PHP source code in filename with PHP comments and whitespace removed. This may be useful for determining the amount of actual code in your scripts compared with the amount of comments. This is similar to using php -w from the commandline.
This function works as described as of PHP 5.0.1. Before this it would only return an empty string. For more information on this bug and its prior behavior, see bug report » #29606.
// PHP comment here
* Another PHP comment
// Newlines are considered whitespace, and are removed too:
echo php_strip_whitespace(__FILE__); do_nothing(); ?>
Notice the PHP comments are gone, as are the whitespace and newline after the first echo statement.