Trying to wrap <span> around first word of multiple word strings only works on two word strings and not more than two

Question

I am trying to wrap a around the first word of multiple word widget titles. I have used the answer from here:

Revised Wordpress function to put a Span around the first word of the Title?

and adjusted it to look like:

function add_label_to_post_title( $title = '' ) {
    $ARR_title = explode(" ", $title);

    if(sizeof($ARR_title) > 1 ) {
        $first_word = "<span>".$ARR_title['0']."</span> ";
        unset($ARR_title['0']);
        return $first_word. implode(" ", $ARR_title);
    } else {
        return $title;
    }
}

add_filter( 'widget_title', 'add_label_to_post_title' );

and it works great on two word titles. However 3 or more word titles are not affected.

I tried modifying the code with:

preg_replace('/(?<=\>)\b\w*\b|^\w*\b/', '<span>$0</span>', $string);

from here:

wrap <b>-tag around first word of string with preg_replace

and had the same result, works great on two word titles but three or more are not affected. Does anyone have any idea why?

Answer 1

Please find code snippet using array below

function add_label_to_post_title( $title = '' ) 
{

    $ARR_title = explode(" ", $title);

    if(sizeof($ARR_title) > 1 )
    {
        $ARR_title[0] = "<span>".$ARR_title[0]."</span>";
        return implode(" ", $ARR_title);
    }
    else
    {
        return $title;
    }

}
echo add_label_to_post_title ("hi there this is test code");