Making anonymous functions from PHP 5.3 work with PHP 5.2

Question

I have an anonymous functions that I now need to update to be compatible with PHP 5.2. The function (below) takes text and uppercases the first letter of every sentence.

Answer 1

preg_replace_callback() as a second argument requires a callable, that is a function itself, not a returned value from a function.

So just replace, upper_case($input) with upper_case, so it would look like this

preg_replace_callback('/([.!?])\s*(\w)/', 'upper_case', ucfirst(strtolower($input)));