further diff improvements.

CLAUDE.md

@@ -0,0 +1,70 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+This is an Effect-based TypeScript implementation of the Monkey programming language interpreter from "Writing An Interpreter In Go", with extensions for symbolic differentiation. The project includes:
+
+- A complete lexer, parser, and evaluator for the Monkey language
+- Symbolic differentiation capabilities supporting constant, sum, power, product, quotient, and chain rules
+- A web-based REPL interface built with React and Vite
+- Trigonometric derivatives implementation
+
+## Development Commands
+
+### Core Development
+- `pnpm test` - Run tests with Bun
+- `pnpm vitest` - Run tests with Vitest
+- `pnpm coverage` - Generate test coverage reports
+- `pnpm check` - TypeScript type checking
+- `pnpm lint` - Run ESLint on codebase
+- `pnpm lint-fix` - Auto-fix lint issues
+
+### Application
+- `pnpm repl` - Start the CLI REPL interface
+- `pnpm dev` - Start Vite development server for web interface
+- `pnpm build` - Build the project
+
+### Testing
+- Run single test file: `bunx vitest src/tests/vitest/eval/eval.test.ts`
+- Run specific test pattern: `bunx vitest --grep "pattern"`
+
+## Architecture
+
+### Core Services (Effect-based)
+The interpreter follows a traditional lexer → parser → evaluator pipeline, implemented using Effect-TS:
+
+- **Lexer** (`src/services/lexer/`) - Tokenizes input strings using state management services
+- **Parser** (`src/services/parser/`) - Builds AST from tokens with precedence-based parsing
+- **Evaluator** (`src/services/evaluator/`) - Interprets AST nodes and manages runtime environment
+
+### Schema System
+The codebase uses a comprehensive schema system in `src/schemas/`:
+- `nodes/` - AST node definitions (expressions, statements, program)
+- `objs/` - Runtime object representations 
+- `token/` - Token type definitions
+- Built-in function schemas and differentiation schemas
+
+### Key Architectural Patterns
+- **Effect Services**: Core functionality implemented as Effect services with dependency injection
+- **Schema Validation**: Extensive use of Effect Schema for type-safe parsing and validation
+- **Functional Programming**: Immutable data structures and functional composition throughout
+- **Error Handling**: Effect-based error handling with typed error channels
+
+### Differentiation Engine
+Located in `src/services/diff/`, implements symbolic differentiation:
+- `obj.ts` - Core differentiation logic for different object types
+- `helper.ts` - Utility functions for differentiation operations
+- Supports polynomial objects and various mathematical operations
+
+### Testing Structure
+- Unit tests in `src/tests/vitest/` organized by functionality
+- Parser tests focus on AST construction correctness
+- Evaluator tests verify runtime behavior and differentiation accuracy
+- Helper utilities in test directories for common test patterns
+
+## Entry Points
+- CLI REPL: `src/services/cli.ts`
+- Web interface: `src/vite/main.tsx`
+- Core interpreter: `src/services/evaluator/index.ts`

package.json

@@ -19,63 +19,63 @@
 		"build": "vite build"
 	},
 	"dependencies": {
-		"@biomejs/biome": "1.9.4",
-		"@effect/cli": "0.54.1",
-		"@effect/opentelemetry": "0.42.7",
-		"@effect/platform": "0.75.1",
-		"@effect/platform-bun": "0.55.1",
-		"@effect/platform-node": "0.71.1",
-		"@opentelemetry/exporter-trace-otlp-http": "0.57.1",
-		"@opentelemetry/sdk-metrics": "1.30.1",
-		"@opentelemetry/sdk-trace-base": "1.30.1",
-		"@opentelemetry/sdk-trace-node": "1.30.1",
-		"@opentelemetry/sdk-trace-web": "1.30.1",
-		"@tailwindcss/vite": "^4.0.6",
-		"@types/react": "^19.0.9",
-		"@types/react-dom": "^19.0.3",
-		"@vitejs/plugin-react-swc": "^3.8.0",
+		"@biomejs/biome": "2.1.2",
+		"@effect/cli": "0.68.0",
+		"@effect/opentelemetry": "0.55.0",
+		"@effect/platform": "0.89.0",
+		"@effect/platform-bun": "0.75.0",
+		"@effect/platform-node": "0.92.0",
+		"@opentelemetry/exporter-trace-otlp-http": "0.203.0",
+		"@opentelemetry/sdk-metrics": "2.0.1",
+		"@opentelemetry/sdk-trace-base": "2.0.1",
+		"@opentelemetry/sdk-trace-node": "2.0.1",
+		"@opentelemetry/sdk-trace-web": "2.0.1",
+		"@tailwindcss/vite": "^4.1.11",
+		"@types/react": "^19.1.8",
+		"@types/react-dom": "^19.1.6",
+		"@vitejs/plugin-react-swc": "^3.11.0",
 		"class-variance-authority": "^0.7.1",
 		"clsx": "^2.1.1",
-		"effect": "3.12.7",
+		"effect": "3.17.0",
 		"eval": "0.1.8",
-		"lucide-react": "^0.475.0",
-		"nerdamer-prime": "^1.2.4",
-		"react": "^19.0.0",
-		"react-dom": "^19.0.0",
-		"tailwind-merge": "^3.0.1",
+		"lucide-react": "^0.525.0",
+		"nerdamer-prime": "^1.2.5",
+		"react": "^19.1.0",
+		"react-dom": "^19.1.0",
+		"tailwind-merge": "^3.3.1",
 		"tailwindcss-animate": "^1.0.7"
 	},
 	"devDependencies": {
-		"@babel/cli": "7.26.4",
-		"@babel/core": "7.26.7",
-		"@babel/plugin-transform-export-namespace-from": "7.25.9",
-		"@babel/plugin-transform-modules-commonjs": "7.26.3",
-		"@effect/build-utils": "0.7.8",
-		"@effect/eslint-plugin": "0.2.0",
-		"@effect/language-service": "0.2.0",
-		"@effect/vitest": "0.17.3",
-		"@eslint/compat": "1.2.5",
-		"@eslint/eslintrc": "3.2.0",
-		"@eslint/js": "9.19.0",
-		"@types/bun": "1.2.0",
-		"@types/node": "22.10.10",
-		"@typescript-eslint/eslint-plugin": "8.21.0",
-		"@typescript-eslint/parser": "8.21.0",
-		"@vitest/coverage-v8": "3.0.7",
-		"autoprefixer": "^10.4.20",
+		"@babel/cli": "7.28.0",
+		"@babel/core": "7.28.0",
+		"@babel/plugin-transform-export-namespace-from": "7.27.1",
+		"@babel/plugin-transform-modules-commonjs": "7.27.1",
+		"@effect/build-utils": "0.8.9",
+		"@effect/eslint-plugin": "0.3.2",
+		"@effect/language-service": "0.28.0",
+		"@effect/vitest": "0.25.0",
+		"@eslint/compat": "1.3.1",
+		"@eslint/eslintrc": "3.3.1",
+		"@eslint/js": "9.31.0",
+		"@types/bun": "1.2.19",
+		"@types/node": "24.0.15",
+		"@typescript-eslint/eslint-plugin": "8.38.0",
+		"@typescript-eslint/parser": "8.38.0",
+		"@vitest/coverage-v8": "3.2.4",
+		"autoprefixer": "^10.4.21",
 		"babel-plugin-annotate-pure-calls": "0.5.0",
-		"eslint": "9.19.0",
-		"eslint-import-resolver-typescript": "3.7.0",
-		"eslint-plugin-codegen": "0.29.0",
-		"eslint-plugin-import": "2.31.0",
+		"eslint": "9.31.0",
+		"eslint-import-resolver-typescript": "4.4.4",
+		"eslint-plugin-codegen": "0.33.0",
+		"eslint-plugin-import": "2.32.0",
 		"eslint-plugin-simple-import-sort": "12.1.1",
 		"eslint-plugin-sort-destructure-keys": "2.0.0",
-		"postcss": "^8.5.2",
-		"tailwindcss": "^4.0.6",
-		"tsx": "4.19.2",
-		"typescript": "5.7.3",
-		"vite": "^6.1.0",
-		"vitest": "3.0.4"
+		"postcss": "^8.5.6",
+		"tailwindcss": "^4.1.11",
+		"tsx": "4.20.3",
+		"typescript": "5.8.3",
+		"vite": "^7.0.5",
+		"vitest": "3.2.4"
 	},
 	"effect": {
 		"generateExports": {

src/schemas/objs/call.ts

@@ -2,20 +2,21 @@
 
 import { Schema } from "effect";
 import type { BuiltInFunc } from "../built-in";
-import { Exp } from "../nodes/exps/union";
+import type { Exp } from "../nodes/exps/union";
 import { BuiltInObj } from "./built-in";
 import { FunctionObj, type FunctionObjEncoded } from "./function";
+import { Obj, type ObjEncoded } from "./union";
 
 export interface CallObj {
 	readonly _tag: "CallObj";
 	readonly fn: FunctionObj | BuiltInObj;
-	readonly args: readonly Exp[];
+	readonly args: readonly Obj[];
 }
 
 export interface CallObjEncoded {
 	readonly _tag: "CallObj";
 	readonly fn: FunctionObjEncoded | BuiltInObj;
-	readonly args: readonly Exp[];
+	readonly args: readonly ObjEncoded[];
 }
 
 export const CallObj = Schema.TaggedStruct("CallObj", {
@@ -25,10 +26,10 @@ export const CallObj = Schema.TaggedStruct("CallObj", {
 			FunctionObjEncoded | BuiltInObj
 		> => Schema.Union(FunctionObj, BuiltInObj),
 	),
-	args: Schema.Array(Schema.suspend((): Schema.Schema<Exp> => Exp)),
+	args: Schema.Array(Schema.suspend((): Schema.Schema<Obj, ObjEncoded> => Obj)),
 });
 
-export const BuiltInCallObj = (fn: BuiltInFunc) => (args: readonly Exp[]) =>
+export const BuiltInCallObj = (fn: BuiltInFunc) => (args: readonly Obj[]) =>
 	CallObj.make({
 		fn: BuiltInObj.make({ fn }),
 		args,