Best Way To Concatenate Strings In PHP With Spaces In Between

Question

I need to concatenate an indeterminate number of strings, and I would like a space in between two adjoining strings. Like so a b c d e f.

Also I do not want

Answer 1

function concatenate()
{
    $return = array();
    $numargs = func_num_args();
    $arg_list = func_get_args();
    for($i = 0; $i < $numargs; $i++)
    {
        if(empty($arg_list[$i])) continue;
        $return[] = trim($arg_list[$i]);
    }
    return implode(' ', $return);
}

echo concatenate("Mark ", " as ", " correct");