Ledger types handlers

covenant.cabal

@@ -85,6 +85,7 @@ library
     Control.Monad.HashCons
     Covenant.ASG
     Covenant.Constant
+    Covenant.Ledger
     Covenant.Prim
 
   other-modules:

src/Covenant/ASG.hs

@@ -24,7 +24,7 @@ module Covenant.ASG
     Bound,
     Ref (..),
     PrimCall (..),
-    ASGNode (Lit, Lam, Prim, App, Let),
+    ASGNode (Lit, Lam, Prim, App, Let, LedgerAccess, LedgerDestruct),
     Scope,
     ASG,
     ASGNeighbourhood,
@@ -43,6 +43,8 @@ module Covenant.ASG
     app,
     lam,
     letBind,
+    ledgerAccess,
+    ledgerDestruct,
 
     -- ** Compile
     compileASG,
@@ -91,18 +93,29 @@ import Covenant.Internal.ASG
     viewASGZipper,
   )
 import Covenant.Internal.ASGNode
-  ( ASGNode (AppInternal, LamInternal, LetInternal, LitInternal, PrimInternal),
+  ( ASGNode
+      ( AppInternal,
+        LamInternal,
+        LedgerAccessInternal,
+        LedgerDestructInternal,
+        LetInternal,
+        LitInternal,
+        PrimInternal
+      ),
     Arg (Arg),
     Bound (Bound),
     Id,
     PrimCall (PrimCallOne, PrimCallSix, PrimCallThree, PrimCallTwo),
     Ref (ABound, AnArg, AnId),
     pattern App,
     pattern Lam,
+    pattern LedgerAccess,
+    pattern LedgerDestruct,
     pattern Let,
     pattern Lit,
     pattern Prim,
   )
+import Covenant.Ledger (LedgerAccessor, LedgerDestructor)
 import Data.Kind (Type)
 import Data.Monoid (Endo (Endo))
 import Data.Proxy (Proxy (Proxy))
@@ -243,6 +256,31 @@ letBind Scope r f = do
   res <- f Scope
   refTo . LetInternal r $ res
 
+-- | Construct a ledger type accessor.
+--
+-- @since 1.0.0
+ledgerAccess ::
+  forall (m :: Type -> Type).
+  (MonadHashCons Id ASGNode m) =>
+  LedgerAccessor ->
+  Ref ->
+  m Id
+ledgerAccess acc = refTo . LedgerAccessInternal acc
+
+-- | Construct a ledger sum type destructor. The first 'Ref' must be a
+-- function suitable for destructuring the second 'Ref', though we do not
+-- currently check this.
+--
+-- @since 1.0.0
+ledgerDestruct ::
+  forall (m :: Type -> Type).
+  (MonadHashCons Id ASGNode m) =>
+  LedgerDestructor ->
+  Ref ->
+  Ref ->
+  m Id
+ledgerDestruct d rFun = refTo . LedgerDestructInternal d rFun
+
 -- | The possible moves in the 'ASGZipper' wrapper monad. These need to be
 -- wrapped in 'ASGMoves' to make them usable with the update monad
 -- implementation: see 'moveASGView' for a helper avoiding this.

src/Covenant/Internal/ASGNode.hs

@@ -12,11 +12,14 @@ module Covenant.Internal.ASGNode
     pattern Lam,
     pattern Let,
     pattern App,
+    pattern LedgerAccess,
+    pattern LedgerDestruct,
     childIds,
   )
 where
 
 import Covenant.Constant (AConstant)
+import Covenant.Ledger (LedgerAccessor, LedgerDestructor)
 import Covenant.Prim (OneArgFunc, SixArgFunc, ThreeArgFunc, TwoArgFunc)
 import Data.Maybe (mapMaybe)
 import Data.Word (Word64)
@@ -124,6 +127,8 @@ data ASGNode
   | LamInternal Ref
   | LetInternal Ref Ref
   | AppInternal Ref Ref
+  | LedgerAccessInternal LedgerAccessor Ref
+  | LedgerDestructInternal LedgerDestructor Ref Ref
   deriving stock
     ( -- | @since 1.0.0
       Eq,
@@ -165,7 +170,20 @@ pattern Let rBind rBody <- LetInternal rBind rBody
 pattern App :: Ref -> Ref -> ASGNode
 pattern App rFun rArg <- AppInternal rFun rArg
 
-{-# COMPLETE Lit, Prim, Lam, Let, App #-}
+-- | An accessor for a ledger type.
+--
+-- @since 1.0.0
+pattern LedgerAccess :: LedgerAccessor -> Ref -> ASGNode
+pattern LedgerAccess acc rArg <- LedgerAccessInternal acc rArg
+
+-- | A destructor for a ledger sum. The first 'Ref' is for a destructor
+-- function, while the second is the argument to be destructured.
+--
+-- @since 1.0.0
+pattern LedgerDestruct :: LedgerDestructor -> Ref -> Ref -> ASGNode
+pattern LedgerDestruct d rDest rArg <- LedgerDestructInternal d rDest rArg
+
+{-# COMPLETE Lit, Prim, Lam, Let, App, LedgerAccess, LedgerDestruct #-}
 
 -- | @since 1.0.0
 childIds :: ASGNode -> [Id]
@@ -179,6 +197,8 @@ childIds = \case
   LamInternal r1 -> mapMaybe refToId [r1]
   LetInternal r1 r2 -> mapMaybe refToId [r1, r2]
   AppInternal r1 r2 -> mapMaybe refToId [r1, r2]
+  LedgerAccessInternal _ r1 -> mapMaybe refToId [r1]
+  LedgerDestructInternal _ r1 r2 -> mapMaybe refToId [r1, r2]
 
 -- Helpers
 

src/Covenant/Ledger.hs

@@ -0,0 +1,45 @@
+module Covenant.Ledger
+  ( LedgerAccessor (..),
+    LedgerDestructor (..),
+  )
+where
+
+import Data.Text (Text)
+
+-- | A way of accessing a ledger type's field(s).
+--
+-- @since 1.0.0
+data LedgerAccessor
+  = -- | For a type with a single field and a single variant, accesses that field.
+    LedgerUnwrap
+  | -- For a type with a single variant and multiple named fields, accesses the field named.
+    LedgerField Text
+  deriving stock
+    ( -- | @since 1.0.0
+      Eq,
+      -- | @since 1.0.0
+      Ord,
+      -- | @since 1.0.0
+      Show
+    )
+
+-- | A destructor for a sum type from the ledger.
+--
+-- @since 1.0.0
+data LedgerDestructor
+  = DestructorDRep
+  | DestructorDelegatee
+  | DestructorTxCert
+  | DestructorVoter
+  | DestructorVote
+  | DestructorGovernanceAction
+  | DestructorScriptPurpose
+  | DestructorScriptInfo
+  deriving stock
+    ( -- | @since 1.0.0
+      Eq,
+      -- | @since 1.0.0
+      Ord,
+      -- | @since 1.0.0
+      Show
+    )