Fix drifted handwritten tycon constants found by tconcheck

Bring all nine drifted constants in line with the Prelude-derived truth
(the checker's DRIFT output was used as the spec), and empty the
tconcheck knownDrift waiver list; the waiver mechanism remains for
future incidents but ships empty.

  * Type.hs tInt/tUInt: TIabstract -> TIdata (Prelude declares
    'data Int n = Int (Bit n)' and likewise UInt)
  * Type.hs tPrimPair (and StdPrel tiPair, used by itPrimPair):
    SStruct -> SInterface [] (PrimPair is declared as an interface)
  * Type.hs tActionValue: old struct sort -> TIdata [ActionValue]
    ('data ActionValue a = ActionValue ...')
  * Type.hs tActionValue_: field names __value/__action ->
    avValue_/avAction_ (new PreIds position variants added)
  * Type.hs tFile: TIabstract -> TIdata [InvalidFile, MCD, FD]
    (new PreStrings/PreIds constructor ids added)
  * ISyntaxUtil itInout: kind # -> * (apparently copied from itInout_)
    corrected to * -> *
  * ISyntaxUtil itPrimPair: kind was left-nested, (* -> *) -> *,
    because IKFun had no fixity declaration and defaulted to infixl 9;
    IType.hs now declares infixr 8 `IKFun` (matching Kind's right-nested
    Kfun and IConv.iConvK).  Census of every backticked IKFun chain in
    the tree: itPrimPair was the only unparenthesized multi-arrow chain;
    all others are single-arrow or already explicitly parenthesized, so
    the fixity change reparses nothing else.
  * StdPrel tiBufferMode (used by itBufferMode): tiEnum -> tiData
    (BlockBuffering carries a Maybe Integer argument, so BufferMode is
    not an enum)

The corresponding position-parameterized variants (tIntAt,
tActionValueAt, tActionValue_At) are fixed to the same payloads.

A consumer audit found no reader of these payloads out of the constants
themselves: comparison sites use Eq/Ord (which compare by qualified Id)
or wildcard the payload fields in patterns; the payloads only travel
into generated ISyntax via iConvT, where they now agree with what
symtab-derived types already carried.

tconcheck now reports all 94 entries OK with zero waived.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LVL9ornS6uf9hVxAuL7GhK

Author: nanavati

src/comp/ISyntaxUtil.hs

@@ -61,7 +61,7 @@ itReal = ITCon idReal IKStar tiReal
 itClock, itReset, itInout, itInout_ :: IType
 itClock = ITCon idClock IKStar tiClock
 itReset = ITCon idReset IKStar tiReset
-itInout  = ITCon idInout  (IKNum `IKFun` IKStar) tiInout
+itInout  = ITCon idInout  (IKStar `IKFun` IKStar) tiInout
 itInout_ = ITCon idInout_ (IKNum `IKFun` IKStar) tiInout
 
 itInoutT :: IType -> IType

src/comp/IType.hs

@@ -31,6 +31,12 @@ import qualified Data.Generics as Generic
 -- ==============================
 -- IKind, IType
 
+-- Arrow kinds nest to the right (matching Kind's Kfun and IConv.iConvK),
+-- so backticked IKFun chains must associate to the right.  Without this
+-- declaration the default infixl 9 silently built left-nested (wrong)
+-- kinds; tconcheck caught exactly that in itPrimPair.
+infixr 8 `IKFun`
+
 data IKind
         = IKStar
         | IKNum

src/comp/PreIds.hs

@@ -120,6 +120,11 @@ idInvalid = prelude_id_no fsInvalid
 idValid = prelude_id_no fsValid
 idEmpty = prelude_id_no fsEmptyIfc
 idFile = prelude_id_no fsFile
+-- constructors of the File type
+idInvalidFile, idMCD, idFD :: Id
+idInvalidFile = prelude_id_no fsInvalidFile
+idMCD = prelude_id_no fsMCD
+idFD = prelude_id_no fsFD
 idEither, idLeft, idRight :: Id
 idEither = prelude_id_no fsEither
 idLeft = prelude_id_no fsLeft
@@ -138,6 +143,9 @@ idActionValue_ = prelude_id_no fsActionValue_
 idAVValue_, idAVAction_ :: Id
 idAVValue_ = prelude_id_no fsAVValue_
 idAVAction_ = prelude_id_no fsAVAction_
+idAVValue_at, idAVAction_at :: Position -> Id
+idAVValue_at pos = prelude_id pos fsAVValue_
+idAVAction_at pos = prelude_id pos fsAVAction_
 
 -- names of the special selector functions in the Prelude
 id__value, id__action :: Id

src/comp/PreStrings.hs

@@ -502,6 +502,12 @@ fsBitsToReal   = mkFString "$bitstoreal"
 
 fsFile = mkFString "File"
 
+-- | Constructors of the File type in the Prelude
+fsInvalidFile, fsMCD, fsFD :: FString
+fsInvalidFile = mkFString "InvalidFile"
+fsMCD = mkFString "MCD"
+fsFD = mkFString "FD"
+
 
 -- | Classes hardcoded in the Prelude which were added for ContextErrors
 fsBitwise, fsBitReduce, fsBitExtend, fsArith, fsOrd :: FString

src/comp/StdPrel.hs

@@ -1053,7 +1053,7 @@ tiInout   = TIabstract
 tiPrimArray = TIabstract
 
 tiPair, tiBool, tiAction, tiRules, tiString, tiChar :: TISort
-tiPair    = TIstruct SStruct [idPrimFst, idPrimSnd]
+tiPair    = TIstruct (SInterface []) [idPrimFst, idPrimSnd]
 tiBool    = tiEnum [idFalse, idTrue]
 tiAction  = TIabstract
 tiRules   = TIabstract
@@ -1062,7 +1062,7 @@ tiChar    = TIabstract
 
 tiHandle, tiBufferMode, tiMaybe, tiList, tiFmt :: TISort
 tiHandle  = TIabstract
-tiBufferMode = tiEnum [idNoBuffering, idLineBuffering, idBlockBuffering]
+tiBufferMode = tiData [idNoBuffering, idLineBuffering, idBlockBuffering]
 tiMaybe   = tiData [idInvalid, idValid]
 tiList    = tiData [idNil noPosition, idCons noPosition]
 tiFmt     = TIabstract

src/comp/Type.hs

@@ -10,20 +10,20 @@ infixr 4 `fn`
 
 -- XXX these definitions should be synced with StdPrel.hs where applicable
 
+tiData, tiEnum :: [Id] -> TISort
+tiEnum cons = TIdata { tidata_cons = cons, tidata_enum = True }
+tiData cons = TIdata { tidata_cons = cons, tidata_enum = False }
+
 tArrow, tBit, tInt :: Type
 tArrow = TCon (TyCon (idArrow noPosition) (Just (Kfun KStar (Kfun KStar KStar))) TIabstract)
 tBit = TCon (TyCon idBit (Just (Kfun KNum KStar)) TIabstract)
-tInt = TCon (TyCon idInt (Just (Kfun KNum KStar)) TIabstract)
+tInt = TCon (TyCon idInt (Just (Kfun KNum KStar)) (tiData [idInt]))
 
 tIntAt :: Position -> Type
-tIntAt pos = TCon (TyCon (idIntAt pos) (Just (Kfun KNum KStar)) TIabstract)
-
-tiData, tiEnum :: [Id] -> TISort
-tiEnum cons = TIdata { tidata_cons = cons, tidata_enum = True }
-tiData cons = TIdata { tidata_cons = cons, tidata_enum = False }
+tIntAt pos = TCon (TyCon (idIntAt pos) (Just (Kfun KNum KStar)) (tiData [idIntAt pos]))
 
 tUInt, tBool, tPrimUnit :: Type
-tUInt = TCon (TyCon idUInt (Just (Kfun KNum KStar)) TIabstract)
+tUInt = TCon (TyCon idUInt (Just (Kfun KNum KStar)) (tiData [idUInt]))
 tBool = TCon (TyCon idBool (Just KStar) (tiEnum [idFalse, idTrue]))
 --tArray = TCon (TyCon idArray (Just (Kfun KNum (Kfun KNum KStar))) (TIstruct SInterface [id_sub, id_upd]))
 tPrimUnit = TCon (TyCon idPrimUnit (Just KStar) (TIstruct SStruct []))
@@ -55,18 +55,18 @@ tType = TCon (TyCon idType (Just KStar) TIabstract)
 tPred, tAttributes, tPrimPair :: Type
 tPred = TCon (TyCon idPred (Just KStar) TIabstract)
 tAttributes = TCon (TyCon idAttributes (Just KStar) TIabstract)
-tPrimPair = TCon (TyCon idPrimPair (Just (Kfun KStar (Kfun KStar KStar))) (TIstruct SStruct [idPrimFst, idPrimSnd]))
+tPrimPair = TCon (TyCon idPrimPair (Just (Kfun KStar (Kfun KStar KStar))) (TIstruct (SInterface []) [idPrimFst, idPrimSnd]))
 
 tAction, tActionValue, tActionValue_, tAction_:: Type
 tAction = TCon (TyCon idAction (Just KStar) (TItype 0 (TAp tActionValue tPrimUnit)))
-tActionValue = TCon (TyCon idActionValue (Just (Kfun KStar KStar)) (TIstruct SStruct [id__value, id__action]))
-tActionValue_ = TCon (TyCon idActionValue_ (Just (Kfun KStar KStar)) (TIstruct SStruct [id__value, id__action]))
+tActionValue = TCon (TyCon idActionValue (Just (Kfun KStar KStar)) (tiData [idActionValue]))
+tActionValue_ = TCon (TyCon idActionValue_ (Just (Kfun KStar KStar)) (TIstruct SStruct [idAVValue_, idAVAction_]))
 tAction_ = TAp tActionValue_ tPrimUnit
 
 tActionAt, tActionValueAt, tActionValue_At :: Position -> Type
 tActionAt pos = TCon (TyCon (idActionAt pos) (Just KStar) (TItype 0 (TAp (tActionValueAt pos) (tPrimUnitAt pos))))
-tActionValueAt pos = TCon (TyCon (idActionValueAt pos) (Just (Kfun KStar KStar)) (TIstruct SStruct [id__value_at pos, id__action_at pos]))
-tActionValue_At pos = TCon (TyCon (idActionValue_At pos) (Just (Kfun KStar KStar)) (TIstruct SStruct [id__value_at pos, id__action_at pos]))
+tActionValueAt pos = TCon (TyCon (idActionValueAt pos) (Just (Kfun KStar KStar)) (tiData [idActionValueAt pos]))
+tActionValue_At pos = TCon (TyCon (idActionValue_At pos) (Just (Kfun KStar KStar)) (TIstruct SStruct [idAVValue_at pos, idAVAction_at pos]))
 
 tPrimAction, tRules :: Type
 tPrimAction = TCon (TyCon idPrimAction (Just KStar) TIabstract)
@@ -98,7 +98,7 @@ tNat :: Position -> Type
 tNat pos = tBitN 32 pos
 
 tFile, tSvaParam :: Type
-tFile = TCon (TyCon idFile (Just KStar) TIabstract)
+tFile = TCon (TyCon idFile (Just KStar) (tiData [idInvalidFile, idMCD, idFD]))
 tSvaParam  = TCon (TyCon idSvaParam (Just KStar) (tiData [idSvaBool, idSvaNumber]))
 
 fn         :: Type -> Type -> Type

src/comp/tconcheck.hs

@@ -63,35 +63,19 @@ exemptMissing :: [(Id, String)]
 exemptMissing = []
 
 -- Entries confirmed to drift from the Prelude truth, pending direction on
--- the fix.  These are reported loudly (as DRIFT-WAIVED) but do not fail
--- the check, so that the build stays green while the fix is decided.
--- This list should shrink to empty over time; do NOT add new entries to
--- paper over a check failure.
+-- the fix.  Waived entries are reported loudly (as DRIFT-WAIVED) but do
+-- not fail the check, so that the build can stay green while a fix is
+-- decided.  Keep this list EMPTY; do NOT add entries to paper over a
+-- check failure.
 --
--- All of the entries below are pre-existing: they have been masked for
--- years by the fact that TyCon Eq/Ord ignore the sort and ITCon
--- comparisons ignore both kind and sort (see CType.hs and IType.hs).
+-- (The nine pre-existing drifts this checker originally found -- masked
+-- for years by the payload-ignoring TyCon/ITCon comparisons -- were
+-- fixed in the commit that emptied this list: Int/UInt/File/ActionValue
+-- sorts, ActionValue_ field names, PrimPair's SInterface sort, itInout's
+-- kind, itPrimPair's kind via the IKFun fixity declaration, and
+-- BufferMode's enum flag.)
 knownDrift :: [(String, String)]  -- (section ++ " " ++ name, reason)
-knownDrift =
-    [ ("Type Prelude.Int",
-       "Prelude.bs declares 'data Int n = Int (Bit n)'; handwritten sort predates it (TIabstract)")
-    , ("Type Prelude.UInt",
-       "Prelude.bs declares 'data UInt n = UInt (Bit n)'; handwritten sort predates it (TIabstract)")
-    , ("Type Prelude.PrimPair",
-       "Prelude.bs declares PrimPair as an interface (TIstruct (SInterface []) ...); handwritten sort says SStruct")
-    , ("Type Prelude.ActionValue",
-       "Prelude.bs declares 'data ActionValue a = ActionValue ...'; handwritten sort is the old struct representation")
-    , ("Type Prelude.ActionValue_",
-       "ActionValue_ field names are avValue_/avAction_ in Prelude.bs; handwritten sort has the old __value/__action")
-    , ("Type Prelude.File",
-       "Prelude.bs declares 'data File = InvalidFile | MCD .. | FD ..'; handwritten sort predates it (TIabstract)")
-    , ("ISyntaxUtil Prelude.Inout",
-       "itInout has kind # -> * (apparently copied from itInout_); Inout's kind is * -> *")
-    , ("ISyntaxUtil Prelude.PrimPair",
-       "itPrimPair's kind is left-nested, (* -> *) -> *, because IKFun has no fixity declaration (defaults to infixl 9); also the SStruct-vs-SInterface sort, as in Type.hs")
-    , ("ISyntaxUtil Prelude.BufferMode",
-       "BlockBuffering carries a Maybe Integer argument, so BufferMode is not an enum; tiBufferMode says tiEnum")
-    ]
+knownDrift = []
 
 -- -------------------------
 -- Verdicts