[byoung2]

I use structures like this in PHP5 all the time:

  $object->doThis()->doThat()->doTheOther();

But maybe he is referring to method chaining using PHP's built-in functions. There isn't a way that I'm aware of to do the following (short of wrapping the built-in functions with your own classes):

  $string->preg_replace("/[^A-Za-z]+/","_")->trim()->upper();

[seldo]

Precisely what I meant, thanks for clarifying.

[BerislavLopac]

But this is not method chaining, that's simple function nesting, and can easily be done as:

$string = preg_replace("/[^A-Za-z]+/","_", trim(upper($string)));

Or am I missing your point?