Is Never Applicable hook
Use this hook to indicate if the field is never applicable. If a field is never applicable the field is made invisible at startup of a session. A field can become never applicable based on a static constraint, such as a parameter setting.
Example:
function extern boolean tcmcs004.cdf_city.is.never.applicable(long mode)
{
select txmcs000.icty
from txmcs000
where txmcs000.sequ = 0
as set with 1 rows
selectdo
if txmcs000.icty = tcyesno.no then
return(true)
endif
endselect
return(false)
}