adjust public interface: public items should all be stable

`OperandCode` (obviously) wildly varies depending on how i feel on a
given week, so it's now hidden to avoid people depending on numerical
values of its discriminants.

`RegisterBank` got a similar treatment with a new `RegisterClass` struct
that's suitable for public use.

1 files changed, 1 insertions, 1 deletions

diff --git a/test/protected_mode/mod.rs b/test/protected_mode/mod.rs
index bf9315c..c5c3c7b 100644
--- a/test/protected_mode/mod.rs
+++ b/test/protected_mode/mod.rs
@@ -12,7 +12,7 @@ fn test_invalid(data: &[u8]) {
 
 fn test_invalid_under(decoder: &InstDecoder, data: &[u8]) {
     if let Ok(inst) = decoder.decode(data.into_iter().cloned()) {
-        assert_eq!(inst.opcode, Opcode::Invalid, "decoded {:?} from {:02x?} under decoder {}", inst.opcode, data, decoder);
+        assert_eq!(inst.opcode(), Opcode::Invalid, "decoded {:?} from {:02x?} under decoder {}", inst.opcode(), data, decoder);
     } else {
         // this is fine
     }