fn test_isnil_byteptr(){
pb := byteptr(0)
assert isnil( pb )
}
fn test_isnil_voidptr(){
pv := voidptr(0)
assert isnil( pv )
fn test_isnil_charptr(){
pc := &char(0)
assert isnil( pc )
fn test_isnil_intptr(){
pi := &int(0)
assert isnil( pi )