src/Callbacks/AbstractCallback.php
protected function getValue($name, $default = null, callable $callback = null)
    {
        return $this->getSubject()->getValue($name, $default, $callback);
    }
protected function getValue($name, $default = null, callable $callback = null)
    {
        return $this->getSubject()->getValue($name, $default, $callback);
    }
Resolve's the value with the passed colum name from the actual row. If a callback will
be passed, the callback will be invoked with the found value as parameter. If
the value is NULL or empty, the default value will be returned.

@param string        $name     The name of the column to return the value for
@param mixed|null    $default  The default value, that has to be returned, if the row's value is empty
@param callable|null $callback The callback that has to be invoked on the value, e. g. to format it

@return mixed|null The, almost formatted, value