src/Primitive/Container/Container.php
public function truly($recursive = false, $function = null)
    {
        $recursive = $this->getBoolable($recursive);

        $function = $this->getSearchable($function, null);

        if (is_null($function) || ! $function instanceof Closure)
        {
            $function = function ($item) {return ! empty($item);};
        }

        return new static($this->filter($function, $recursive));
    }
public function truly($recursive = false, $function = null)
    {
        $recursive = $this->getBoolable($recursive);

        $function = $this->getSearchable($function, null);

        if (is_null($function) || ! $function instanceof Closure)
        {
            $function = function ($item) {return ! empty($item);};
        }

        return new static($this->filter($function, $recursive));
    }
Remove all not true items from Container (null, '', false, 0, []).
You can specify second argument to make it recursive.

@param bool|BooleanContract $recursive
@param \Closure|string|StringContract|null $function
@return $this