Question

has anybody tried out the new 5.3.0 RC1 php release and played a bit with anonymous functions?

I would like to know if you can use it like python for functional programming.

E.g., can you do something like:

def sinus(x):   if x<=0.1:     return x   else:     return (lambda x: 3*x-4*x*x*x)(sinus(x/3))  print sinus(172.0) 

Or better, can you do all the cool stuff like in python or lisp? Are there any limits? Unfortunately I don´t have a better example in mind. 🙂

Answer 1

The new anonymous functions in PHP 5.3 are very useful in existing callback functions. As this example shows.

echo preg_replace_callback('~-([a-z])~', function ($match) {     return strtoupper($match[1]); }, 'hello-world'); // outputs helloWorld 

It’s still a trick, since PHP 5.3 impliments a Closure class that makes a class instance invokable.

Wikipedia quote:

PHP 5.3 mimics anonymous functions but it does not support true anonymous functions because PHP functions are still not first-class functions.

You can read more about the Closures in this PHP RFC