bitnot op refactoring (#143)

Author: 0xGeorgii

CHANGELOG.md

@@ -178,6 +178,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Compiler
 
+- ast: Remove dead `OperatorKind::BitNot` variant — `~x` is always parsed as `UnaryOperatorKind::BitNot` in a `PrefixUnaryExpression`; the binary enum variant was never produced by the AST builder ([#142])
 - ast: Introduce `SimpleTypeKind` enum for primitive types, replacing string-based type matching ([#50])
 - ast: Simplify Builder API to return `Arena` directly instead of using state machine pattern ([#50])
 - ast: Add error collection in Builder with `collect_errors()` for better parse error reporting ([#50])
@@ -329,3 +330,4 @@ Initial tagged release.
 [#136]: https://github.com/Inferara/inference/pull/136
 [#138]: https://github.com/Inferara/inference/pull/138
 [#140]: https://github.com/Inferara/inference/pull/140
+[#142]: https://github.com/Inferara/inference/pull/142

core/ast/docs/nodes.md

@@ -602,8 +602,6 @@ pub enum OperatorKind {
     BitAnd,   // &
     BitOr,    // |
     BitXor,   // ^
-    BitNot,   // design inconsistency — never produced for BinaryExpression;
-              // the ~ token is always a PrefixUnaryExpression (UnaryOperatorKind::BitNot)
     Shl,      // <<
     Shr,      // >>
 }
@@ -613,10 +611,6 @@ pub enum OperatorKind {
 
 - `Pow` (`**`) is not yet implemented in the WASM backend. Attempting to lower a
   binary expression with this operator will panic with a `todo!()`.
-- `BitNot` should not appear in any `BinaryExpression` node. The `~` token is
-  always parsed as a prefix unary expression and stored as
-  `UnaryOperatorKind::BitNot`. The `OperatorKind::BitNot` variant is a design
-  inconsistency that will be removed in a future cleanup.
 - `And` and `Or` lower to WebAssembly `i32.and`/`i32.or` bitwise instructions.
   Both operands are always evaluated — there is no short-circuit evaluation.
 
@@ -649,7 +643,7 @@ pub enum UnaryOperatorKind {
 ```
 
 Note: `~` always produces a `PrefixUnaryExpression` with `UnaryOperatorKind::BitNot`.
-It is never stored as `OperatorKind::BitNot` in a `BinaryExpression`.
+It is never stored as a `BinaryExpression`.
 
 **Example source:**
 ```inference

core/ast/src/nodes.rs

@@ -405,8 +405,6 @@ pub enum OperatorKind {
     BitOr,
     /// Bitwise XOR: `a ^ b`
     BitXor,
-    /// Bitwise NOT: `~a` (Note: This is actually a unary operator in most contexts)
-    BitNot,
     /// Bitwise left shift: `a << b`
     Shl,
     /// Bitwise right shift: `a >> b`

core/type-checker/src/type_checker.rs

@@ -1436,7 +1436,6 @@ impl TypeChecker {
                         | OperatorKind::BitAnd
                         | OperatorKind::BitOr
                         | OperatorKind::BitXor
-                        | OperatorKind::BitNot
                         | OperatorKind::Shl
                         | OperatorKind::Shr => {
                             if !left_type.is_number() || !right_type.is_number() {

core/wasm-codegen/src/compiler.rs

@@ -889,13 +889,6 @@ impl Compiler {
                      see .claude/plans/codegen/new-pow-operator/master_plan.md"
                 )
             }
-            OperatorKind::BitNot => {
-                todo!(
-                    "OperatorKind::BitNot in binary context — the AST builder never produces \
-                     this; OperatorKind::BitNot is a design inconsistency and should be removed \
-                     from OperatorKind and the type-checker binary arm cleaned up in a separate issue"
-                )
-            }
         };
 
         func.instruction(&instruction);