Here is a modified version that works:
void go_fishing_until_worthless()
{
if ( item_amount( $item[ten-leaf clover]) < 1)
{
while ( item_amount( $item[worthless trinket]) +
item_amount( $item[worthless knick-knack]) +
item_amount( $item[worthless gewgaw])
< 1)
{
buy(1...