Description:
------------
I have an "Array to string conversion" error on the following code.

This occurs only when the method is taken directly in the array. When I use a intermediate variable, there are no error.

Test script:
---------------
<?php

class Foo {
    public function bar() {  echo 'a'; }
}

$foo = new Foo();
foreach ([['bar']] as $test) {
    $method = $test[0];
    $foo->$method();
    // displays "a" ==> success
}

foreach ([['bar']] as $test) {
    $foo->$test[0]();
    // Notice "Array to string conversion" followed by
    // "Function name must be a string"
}