all_fields:exclude merge tag

<?php
// Help Scout 30310 Richard Vav
// exclude field from {all_fields} merge tag by adding
// :exclude to merge tag
add_filter( 'gform_merge_tag_filter', 'exclude_from_all_fields', 10, 4 );
function exclude_from_all_fields ( $value, $merge_tag, $options, $field ) {
    $options_array = explode ( ",", $options );
    $exclude = in_array ( "exclude", $options_array );

// if a field has the CSS Class Name gf_exclude the field will be excluded from the {all_fields:exclude} merge tag
    if ( $merge_tag == "all_fields" && $exclude == true && $field["cssClass"] == "gf_exclude" )
        return false;
    else
        return $value;
}