More generics on expressions

crates/ir/src/lib.rs

@@ -151,6 +151,7 @@ pub struct Expr<T: ProgramInfo> {
 #[cfg_attr(feature = "fuzz", derive_where(Arbitrary; T: ArbitraryProgramInfo))]
 #[cfg_attr(feature = "serde", derive_where(Deserialize, Serialize; T: SerdeProgramInfo))]
 pub enum ExprKind<T: ProgramInfo> {
+    Extra(T::ExprExtra),
     Variable(u32),
     Value(Value),
     Load {
@@ -158,11 +159,11 @@ pub enum ExprKind<T: ProgramInfo> {
         query: Vec<QueryTerm>,
     },
     UnaryOp {
-        op: UnaryOpKind,
+        op: T::UnaryOp,
         term: Arc<Expr<T>>,
     },
     BinaryOp {
-        op: BinaryOpKind,
+        op: T::BinaryOp,
         lhs: Arc<Expr<T>>,
         rhs: Arc<Expr<T>>,
     },
@@ -337,6 +338,15 @@ pub trait ProgramInfo {
 
     /// Metadata for each expression tree node.
     type ExprMeta: Info;
+
+    /// The type of binary operators.
+    type BinaryOp: Info + From<BinaryOpKind> + TryInto<BinaryOpKind>;
+
+    /// The type of unary operators.
+    type UnaryOp: Info + From<UnaryOpKind> + TryInto<UnaryOpKind>;
+
+    /// Extensions to [Expr] past the primitive definitions.
+    type ExprExtra: Info;
 }
 
 /// A blanket trait bounding all associated types in [ProgramInfo].
@@ -356,6 +366,9 @@ macro_rules! def_bound_info {
             RuleMeta: $bounds,
             RuleBodyMeta: $bounds,
             ExprMeta: $bounds,
+            BinaryOp: $bounds,
+            UnaryOp: $bounds,
+            ExprExtra: $bounds,
         >
         {
         }
@@ -368,6 +381,9 @@ macro_rules! def_bound_info {
                 RuleMeta: $bounds,
                 RuleBodyMeta: $bounds,
                 ExprMeta: $bounds,
+                BinaryOp: $bounds,
+                UnaryOp: $bounds,
+                ExprExtra: $bounds,
             >
         {
         }