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Subject: Re: [PHP-DEV] [RFC] Function autoloading through spl_autoload*
From: weierophinney@php.net (Matthew Weier O'Phinney)

On 2011-08-14, Derick Rethans <derick@php.net> wrote:
> On Sat, 6 Aug 2011, Ferenc Kovacs wrote:
> > I would like to introduce this RFC which would provide function
> > autoloading through the spl_autoload facility without userland BC
> > breakage.
> > 
> > https://wiki.php.net/rfc/autofunc
>
> I understand the proposal, but I don't see any compelling reasons in the 
> RFC of why we actually need autoloading for functions? For classes it 
> makes sense because there is almost always a class to file mapping. For 
> functions (and constants) that is not the case, so I am wondering how 
> useful this function autoloading actually is.

Namespaces support the following code types:
 
 * Constants
 * Functions
 * Classes and Interfaces

Currently, autoloading in PHP allows us to dynamically identify and load
only classes and interfaces. However, not all code is written using OOP.
If a developer doesn't want to dive into include/require(_once) hell in
order to use their namespaced functions and/or constants, they have no
real options.

As an example, let's say I've created a procedural CMS or blog of some
sort. In there, I have a file like this:

    <?php
    
    namespace MyProjectName\Posts;
    
    $entries = getEntries(date('Y'));
    foreach ($entries as $entry) {
        displayEntrySummary($entry);
    }

Next, assume the "getEntries" and "displayEntriesSummary" functions are
also in the namespace "MyProjectName\Posts". How does my code load those
functions?

Traditionally, we've used:

    include_once 'MyProjectName/Posts/functions.php';

or

    include_once __DIR__ . '/functions.php';

in our files. But why should we have to do that? Why are functions --
which make up the bulk of PHP's functionality, and which are the
bread-and-butter of many PHP projects -- get second-class status when it
comes to autoloading?

I can see an autoloader like this:

    function autoloadFunctions($funcname, $type = SPL_AUTOLOAD_FUNCTION)
    {
        if (!strstr($funcname, '\\')) {
            // we won't deal with un-namespaced functions
            return false;
        }
        $namespace = substr($funcname, 0, strrpos($funcname, '\\'));
        $funcfile  = str_replace('\\', DIRECTORY_SEPARATOR, $namespace)
                   . DIRECTORY_SEPARATOR . 'Functions.php';
        return include_once($funcfile);
    }

and that might autoload all functions in a given namespace. I've seen
other projects that put a function per-file -- so those might become
even more granular.

Basically, I don't see why we _wouldn't_ want this functionality in PHP.
It makes namespaces practical and useful for procedural applications.

-- 
Matthew Weier O'Phinney
Project Lead            | matthew@zend.com
Zend Framework          | http://framework.zend.com/
PGP key: http://framework.zend.com/zf-matthew-pgp-key.asc