PHP, variable and function in separate files

Question

I have 2 files:

file1 - variables.php

$variable = something;

and file2 - functions.php

function somefunction() {    
    do_something_with $variable;
}

How can I use variable, defined in one file, in function defined in second file?

Answer 1

use include_once / require_once "file2" inside file1 and call the "somefunction" with $variable as argument.