MeTTa TS 1.3.1

Author: MesTTo

RELEASE_NOTES.md

@@ -1,3 +1,38 @@
+# MeTTa TS 1.3.1
+
+MeTTa TS 1.3.1 fixes the type checker's arity check for overloaded operations. An
+operation declared with several signatures is now accepted whenever a call matches
+any of them, not only the last-declared one.
+
+## Fix
+
+`check-types` reported `IncorrectNumberOfArguments` for a call whose argument count
+did not match an operation's last-declared signature, even when another overload
+accepted it. The documentation operation `@return`, for example, is declared both
+`(-> String DocReturnInformal)` and `(-> DocType DocDescription DocReturn)`, so the
+one-string form `(@return "…")` used throughout the standard library and the `das`
+module was wrongly flagged. The applicability check now consults every declared
+signature and, following Hyperon, accepts the call when any overload matches the
+argument count and its argument types. Genuinely wrong arities still error, and
+singly-typed operations are unchanged. This removes a false-positive warning the
+MeTTa LSP surfaced on valid documentation.
+
+## Verification
+
+- The conformance oracle passes all 23 corpus files, byte-identical to 1.3.0.
+- `pnpm test` passes, with a new regression test for overloaded-operation arity.
+- No performance change: the overload lookup runs only when the primary signature's
+  arity does not match, so the common path is untouched (measured within noise).
+
+## Packages
+
+All public packages use version `1.3.1`:
+
+```bash
+npm install @metta-ts/core@1.3.1
+npm install -g @metta-ts/node@1.3.1
+```
+
 # MeTTa TS 1.3.0
 
 MeTTa TS 1.3.0 moves the standard libraries and the debugger engine out of the

packages/browser/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@metta-ts/browser",
-  "version": "1.3.0",
+  "version": "1.3.1",
   "license": "MIT",
   "type": "module",
   "main": "./dist/index.js",

packages/core/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@metta-ts/core",
-  "version": "1.3.0",
+  "version": "1.3.1",
   "license": "MIT",
   "type": "module",
   "main": "./dist/index.js",

packages/core/src/eval.test.ts

@@ -111,4 +111,18 @@ describe("evaluator (smoke)", () => {
 	      !(g a)`;
     expect(first(run(tooFew))).toEqual(["(Error (g a) IncorrectNumberOfArguments)"]);
   });
+
+  it("accepts a call matching any overload of a multiply-typed op", () => {
+    // A multiply-declared op accepts either arity; a count matching a non-last signature must not be flagged
+    // IncorrectNumberOfArguments. This is the mechanism behind the LSP false positive on `@return`'s valid
+    // one-string doc form, which core declares both `(-> String DocReturnInformal)` and `(-> DocType …)`.
+    const decls = `
+	      (: r (-> String Done))
+	      (: r (-> Number Number Done))`;
+    expect(first(run(`${decls}\n!(check-types (r "one"))`))).toEqual(["()"]);
+    expect(first(run(`${decls}\n!(check-types (r 1 2))`))).toEqual(["()"]);
+    expect(first(run(`${decls}\n!(check-types (r))`))).toEqual([
+      "(Error (r) IncorrectNumberOfArguments)",
+    ]);
+  });
 });

packages/core/src/eval.ts

@@ -2190,7 +2190,32 @@ export function checkApplication(
   // precomputed `opSig` it then reuses for partial application, so the signature is looked up once per
   // application.
   if (opSig !== undefined && opSig.length >= 1 && args.length !== opSig.length - 1) {
-    const hasTupleType = (env.types.get(op) ?? []).some((t) => opOf(t) !== "->");
+    const allTypes = env.types.get(op) ?? [];
+    const hasTupleType = allTypes.some((t) => opOf(t) !== "->");
+    // `env.sigs` keeps only the last declaration, but a multiply-typed op has more. `@return`, for example,
+    // is declared both `(-> String DocReturnInformal)` and `(-> DocType DocDescription DocReturn)`, so the
+    // one-string doc form `(@return "…")` is valid even though it does not match the last signature. Hyperon
+    // `check_if_function_type_is_applicable` accepts a call when ANY function type applies, so gather the
+    // overloads that accept this argument count: if one type-checks, the call is applicable.
+    const arityMatches: Atom[][] = [];
+    for (const t of allTypes)
+      if (t.kind === "expr" && opOf(t) === "->" && args.length === t.items.length - 2)
+        arityMatches.push(t.items.slice(1));
+    if (arityMatches.length > 0) {
+      let firstMismatch: [number, Atom, Atom] | undefined;
+      for (const overloadSig of arityMatches) {
+        const overloadMm = typeMismatch(env, w, op, args, overloadSig);
+        if (overloadMm === undefined) return null;
+        firstMismatch ??= overloadMm;
+      }
+      if (hasTupleType || firstMismatch === undefined) return null;
+      const [pos, expected, actual] = firstMismatch;
+      return expr([
+        sym("Error"),
+        expr([sym(op), ...args]),
+        expr([sym("BadArgType"), gint(pos), expected, actual]),
+      ]);
+    }
     // PeTTa-style partial application is allowed for grounded ops. User-declared typed functions keep
     // Hyperon's strict arity errors.
     const underAppliedPartial =

packages/das-client/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@metta-ts/das-client",
-  "version": "1.3.0",
+  "version": "1.3.1",
   "license": "MIT",
   "type": "module",
   "main": "./dist/index.js",

packages/das-gateway/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@metta-ts/das-gateway",
-  "version": "1.3.0",
+  "version": "1.3.1",
   "license": "MIT",
   "type": "module",
   "main": "./dist/index.js",

packages/debug/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@metta-ts/debug",
-  "version": "1.3.0",
+  "version": "1.3.1",
   "license": "MIT",
   "type": "module",
   "main": "./dist/index.js",

packages/edsl/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@metta-ts/edsl",
-  "version": "1.3.0",
+  "version": "1.3.1",
   "author": "MesTTo",
   "license": "MIT",
   "description": "Ergonomic, typed TypeScript eDSL for MeTTa: term builders, tagged templates, host-interop builders, and auto-grounding of TypeScript values.",

packages/grapher/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@metta-ts/grapher",
-  "version": "1.3.0",
+  "version": "1.3.1",
   "author": "MesTTo",
   "license": "MIT",
   "description": "MeTTa visual editor and reduction renderer for browser and Node.js, with node-graph and nested-block views.",