Yajra\Datatables\Html\Builder::encodeCallbackFunctions PHP Method

    protected function encodeCallbackFunctions(array $parameters)
    {
        $callbackFunctions = [];
        foreach ($parameters as $key => $callback) {
            if (in_array($key, $this->validCallbacks)) {
                $callbackFunctions[$key] = $this->compileCallback($callback);
                $parameters[$key] = "#callback_function.{$key}#";
            }
        }
        return [$callbackFunctions, $parameters];
    }