Question

Is it possible to define the same function in two files, include them and then call both function in one go, e.g.

== File1.php ==

function my_function() {
echo "File 1!";
}

== File2.php ==

function my_function() {
echo "File 2!";
}

== File3.php ==

include('File1.php');
include('File2.php');
my_function();

–
Which would output:

File 1!
File 2!

Is this is not possible how would I work around that?

Thanks,
Thomas Edwards

Answer 1

You can’t redefine global functions (outside of runkit, but that’s bad voodoo) so your options remain of using a class driven solution, or an anonymous function driven solution as follows.

You could write a function to assemble all included functions into a call queue (which is simply another anonymous function that runs the queue):

function queueFunctions(array $functions){
    return function() 
    use ($functions) {
        foreach($functions as $function) {
            $function();
        }
    };
}

And return anonymous functions from each of the files as you described, rather than redefine a global function:

file1.php

return function() {
    echo 'Hello';
};

file2.php

return function() {
    echo 'World';
};

Then, you can:

// both
$function = queueFunctions([
    include('file1.php'), 
    include('file2.php'),
]);

$function(); // HelloWorld

// one of them    
$function = queueFunctions([
    include('file2.php'),
]);

$function(); // World

// repeated calls
$function = queueFunctions([
    include('file2.php'),
    include('file1.php'),
    include('file2.php'),
]);

$function(); // WorldHelloWorld