Hello - hope this is the right place to come.
I'm trying to write a shortcode for Wordpress that compares two values, and if they match, generates content. If they don't match, no content is shown.

I'm a proper noob at this, and have tried a few ways, but no success.
The following generates the content, but it's not working.

PHP Code:
function compare_func($atts,$content=""){
    
extract(shortcode_atts(array(
    
'val1' =>'''val2' => '')
    , 
$atts));
    if(
$val1 == $val2)
    
$content '';
    return 
$content;
    }
add_shortcode('compare''compare_func'); 
[compare val1="no" val2="yes"]this is my content[/compare] outputs the conten, whereas only [compare val1="yes" val2="yes"]this is my content[/compare] should output the content. What am I doing wrong? Do I need an else clause (which I'm not sure how to add).

Any help much appreciated… I've got to learn!