public function testMacrosCantConflictBetweenTypes()
 {
     Strings::extend('foobar', function () {
         return 'string';
     });
     Arrays::extend('foobar', function () {
         return 'arrays';
     });
     $this->assertEquals('string', Strings::foobar());
     $this->assertEquals('arrays', Arrays::foobar());
 }