http://php.net/array_map

http://php.net/array_reduce

http://php.net/array_filter

http://php.net/array_walk

http://php.net/call_user_func_array (apply)

http://php.net/create_function (lambda)

PHP is a language that encompasses all useful things in all other languages. Which, I guess, makes it inferior.

Once you have the function name (or an object method array) it can be stored in a variable with any name you want, passed around, etc. You can pretend it's a function all you want; you can check whether it seems like a real function with is_callable; and you can call it via call_user_func or call_user_func_array (this distinction made necessary because PHP lacks Python/Ruby *array unpacking syntax).

Somewhere I have a PHP class that lets you fake closure. You call Closure::Create($real_cb, $state_data) and it gives you a callback that, when called, calls $real_cb with $state_data plus all arguments that it was called with. And if $state_data is an array whose elements were assigned by reference, the 'closed-over' state is mutable.

So overall, it's a good pretense, even if foreach will always be faster than functional style.

By the way - can someone please try something like the following: $width = getimagesize($filename) [0];

The last time I checked, PHP threw a _Parser_Error_ for indexing an array that you just got from a function. Not even arrays feel like first class citizens.

(Pardon me, if this ward has been eliminated in the mean time. I just vividly remember losing some time hunting for a bug because of this 'feature'.)

   $a = 'var';
   $b = 'iable';
   $variable = 'var';
   echo ${$a.$b};

   $filter = array("name", "email");
   foreach($filter as $v) $$v = $_POST[$v];

Python syntax is much cleaner, and with only one way to do things, it's almost always easier to read. I'm a Pythonista now.

    post = {'name': 'ijoshua', 'email': 'spam@example.com', 'extra': 'data'}
    
    filter = ['name', 'email']
    
    for k in filter: locals()[k] = post[k]
    
    print name, email

I was, of course, joking. Having a laugh at some of the obvious weaknesses in PHP, and pointing out that the other three popular dynamic languages go about things differently.

But, all but one of our world-facing websites are PHP applications (we run Wordpress, Joomla, FlySpray, and DokuWiki, our other wiki is the Perl-based TWiki). I'm actually a grudging fan of the language. It does a few things extraordinarily well, and I've been known to recommend that everyone building installable web applications ought to be writing them in PHP because of its pervasive availability.

Don't take it personally, folks. You're not going to convince me that create_function gives PHP first class functions (maybe if you squint a little), but you also don't need to convince me that it serves a niche very well. I don't have to like it, but I certainly have to use it, because it is currently the best tool for a large class of problems.

I actually started in Perl about 8 years ago (well, before that it was just little Galaga and Snake clones in DOS :), so it's kinda my first love. But Perl was eventually too punk rocker for me...

I drank the Ruby kool-aid for a while too (mmm, pickaxe flavour :), and if I were to start fresh in a language without the framework I'm used to now, I would definitely be seriously weighing Ruby vs Python (or maybe finally get up on the functional languages).

Maybe I'm writing Ruby like PHP, but I probably write PHP more like Perl anyway. When I first came to PHP I was disgusted at ideas like "register_globals" and immediately ported CGI.pm and DBI over so I would have something sane to work with in PHP. This was long before PHP had its "superglobals" and even PEAR didn't exist yet back then.