subclass-idbase

toolchain/sem_ir/ids.h

@@ -964,16 +964,16 @@ constexpr LocId LocId::Invalid = LocId(Parse::NodeId::Invalid);
 // `Any[...]` instruction group.
 //
 // This type participates in `Inst::FromRaw` in order to convert from specific
-// instructions to an `Any[...]` instruction group, but does not participate in
-// `Inst::ToRaw` as it's not possible to convert in the other direction:
+// instructions to an `Any[...]` instruction group:
 // - In the case the specific instruction has a field of some `IdKind` in the
 //   same position, the `Any[...]` type will hold its raw value in the
 //   `AnyRawId` field.
 // - In the case the specific instruction has no field in the same position, the
 //   `Any[...]` type will hold a default constructed `AnyRawId` with an invalid
 //   value.
-struct AnyRawId {
-  int32_t raw_id = IdBase::InvalidIndex;
+struct AnyRawId : public IdBase {
+  constexpr AnyRawId() : IdBase(IdBase::InvalidIndex) {}
+  constexpr explicit AnyRawId(int32_t id) : IdBase(id) {}
 };
 
 }  // namespace Carbon::SemIR