refactor: replace zod with TypeScript generics for variable typing

Remove zod runtime dependency since it was only used for type inference,
not runtime validation. The variable API now uses TypeScript generics
directly: `variable<T>()` instead of `variable(z.type())`.

Author: codehz

bun.lock

@@ -54,8 +54,5 @@
   },
   "peerDependencies": {
     "typescript": "^5.9.3"
-  },
-  "dependencies": {
-    "zod": "^4.3.6"
   }
 }

package.json

@@ -1,12 +1,11 @@
 import { describe, expect, test } from "bun:test";
-import { z } from "zod";
 import { compile, expr, variable } from "./index";
 
 describe("compile 单元测试", () => {
   describe("编译输出格式", () => {
     test("基本结构: [变量名数组, ...表达式]", () => {
-      const x = variable(z.number());
-      const y = variable(z.number());
+      const x = variable<number>();
+      const y = variable<number>();
 
       const sum = expr({ x, y })("x + y");
       const result = compile(sum, { x, y });
@@ -17,8 +16,8 @@ describe("compile 单元测试", () => {
     });
 
     test("变量占位符替换", () => {
-      const x = variable(z.number());
-      const y = variable(z.number());
+      const x = variable<number>();
+      const y = variable<number>();
 
       const sum = expr({ x, y })("x + y");
       const result = compile(sum, { x, y });
@@ -28,9 +27,9 @@ describe("compile 单元测试", () => {
     });
 
     test("变量顺序与声明顺序一致", () => {
-      const a = variable(z.number());
-      const b = variable(z.number());
-      const c = variable(z.number());
+      const a = variable<number>();
+      const b = variable<number>();
+      const c = variable<number>();
 
       const expr1 = expr({ a, b, c })("c + b + a");
       const result = compile(expr1, { a, b, c });
@@ -39,8 +38,8 @@ describe("compile 单元测试", () => {
     });
 
     test("相似变量名正确区分", () => {
-      const x = variable(z.number());
-      const xy = variable(z.number());
+      const x = variable<number>();
+      const xy = variable<number>();
 
       // xy 不应该被 x 的替换影响
       const e = expr({ xy, x })("xy + x");
@@ -53,8 +52,8 @@ describe("compile 单元测试", () => {
 
   describe("错误检测", () => {
     test("检测未定义的变量引用", () => {
-      const x = variable(z.number());
-      const y = variable(z.number());
+      const x = variable<number>();
+      const y = variable<number>();
 
       const sum = expr({ x, y })("x + y + z");
 
@@ -64,7 +63,7 @@ describe("compile 单元测试", () => {
     });
 
     test("检测表达式中引用不存在的上下文变量", () => {
-      const x = variable(z.number());
+      const x = variable<number>();
 
       const e1 = expr({ x })("x + 1");
       const e2 = expr({ e1 })("e1 + e2"); // e2 不存在
@@ -77,8 +76,8 @@ describe("compile 单元测试", () => {
 
   describe("内联优化输出", () => {
     test("内联模式减少表达式数量", () => {
-      const x = variable(z.number());
-      const y = variable(z.number());
+      const x = variable<number>();
+      const y = variable<number>();
 
       const sum = expr({ x, y })("x + y");
       const product = expr({ x, y })("x * y");
@@ -92,8 +91,8 @@ describe("compile 单元测试", () => {
     });
 
     test("非内联模式保留所有中间表达式", () => {
-      const x = variable(z.number());
-      const y = variable(z.number());
+      const x = variable<number>();
+      const y = variable<number>();
 
       const sum = expr({ x, y })("x + y");
       const product = expr({ x, y })("x * y");
@@ -111,8 +110,8 @@ describe("compile 单元测试", () => {
 
   describe("AST 规范化", () => {
     test("输出不包含多余空格", () => {
-      const x = variable(z.number());
-      const y = variable(z.number());
+      const x = variable<number>();
+      const y = variable<number>();
 
       // 原始表达式有空格
       const e = expr({ x, y })("x + y * 2");
@@ -123,8 +122,8 @@ describe("compile 单元测试", () => {
     });
 
     test("保留必要的括号", () => {
-      const x = variable(z.number());
-      const y = variable(z.number());
+      const x = variable<number>();
+      const y = variable<number>();
 
       const e = expr({ x, y })("(x + y) * 2");
       const result = compile(e, { x, y });

src/compile.test.ts

@@ -1,4 +1,3 @@
-import { z } from "zod";
 import { collectIdentifiers, generate, parse, type ASTNode } from "./parser";
 import type {
   BranchNode,
@@ -34,7 +33,7 @@ export interface CompileOptions {
 /**
  * 表达式上下文类型约束
  */
-type ExpressionContext = Record<string, Variable<z.ZodType> | Expression<Record<string, unknown>, unknown>>;
+type ExpressionContext = Record<string, Variable | Expression<Record<string, unknown>, unknown>>;
 
 /**
  * 将表达式树编译为可序列化的 JSON 结构
@@ -59,7 +58,7 @@ type ExpressionContext = Record<string, Variable<z.ZodType> | Expression<Record<
  */
 export function compile<TResult>(
   expression: Expression<ExpressionContext, TResult>,
-  variables: Record<string, Variable<z.ZodType>>,
+  variables: Record<string, Variable>,
   options: CompileOptions = {}
 ): CompiledData {
   const { inline = true, shortCircuit = true } = options;
@@ -87,12 +86,11 @@ export function compile<TResult>(
   const visited = new Set<symbol>();
   const visiting = new Set<symbol>();
 
-  for (const [name, variable] of Object.entries(variables)) {
+  for (const [name] of Object.entries(variables)) {
     const id = Symbol(`var:${name}`);
     const node: ExprNode = {
       id,
       tag: "variable",
-      schema: variable.schema,
     };
     nodeMap.set(id, node);
     variableNodes.set(name, node);
@@ -117,7 +115,7 @@ export function compile<TResult>(
 
     // 收集表达式上下文中的所有节点
     for (const [key, contextItem] of Object.entries(expr.context)) {
-      const item = contextItem as Variable<z.ZodType> | Expression<Record<string, unknown>, unknown>;
+      const item = contextItem as Variable | Expression<Record<string, unknown>, unknown>;
       if (item._tag === "variable") {
         const varNode = variableNodes.get(key);
         if (!varNode) {

src/compile.ts

@@ -1,5 +1,4 @@
 import { expect, test } from "bun:test";
-import { z } from "zod";
 import { compile, constant, evaluate, expr, variable } from "./index";
 
 test("constant: 数字常量", () => {
@@ -46,7 +45,7 @@ test("constant: 对象常量", () => {
 
 test("constant: 在表达式中使用常量", () => {
   const PI = constant(3.14159);
-  const radius = variable(z.number());
+  const radius = variable<number>();
   const area = expr({ PI, radius })("PI * radius * radius");
 
   const compiled = compile(area, { radius });
@@ -66,7 +65,7 @@ test("constant: 多个常量组合", () => {
 
 test("constant: 常量与变量混合", () => {
   const multiplier = constant(2);
-  const x = variable(z.number());
+  const x = variable<number>();
   const doubled = expr({ multiplier, x })("multiplier * x");
 
   const compiled = compile(doubled, { x });

src/constant.test.ts

@@ -1,11 +1,10 @@
 import { describe, expect, test } from "bun:test";
-import { z } from "zod";
 import { compile, evaluate, expr, variable } from "./index";
 
 describe("evaluate 单元测试", () => {
   describe("缓存机制", () => {
     test("重复调用使用缓存的求值函数", () => {
-      const x = variable(z.number());
+      const x = variable<number>();
       const sum = expr({ x })("x + 1");
       const compiled = compile(sum, { x });
 
@@ -19,8 +18,8 @@ describe("evaluate 单元测试", () => {
 
   describe("错误处理", () => {
     test("缺少必需变量时抛出错误", () => {
-      const x = variable(z.number());
-      const y = variable(z.number());
+      const x = variable<number>();
+      const y = variable<number>();
 
       const sum = expr({ x, y })("x + y");
       const compiled = compile(sum, { x, y });
@@ -31,9 +30,9 @@ describe("evaluate 单元测试", () => {
     });
 
     test("缺少多个变量时报告第一个", () => {
-      const a = variable(z.number());
-      const b = variable(z.number());
-      const c = variable(z.number());
+      const a = variable<number>();
+      const b = variable<number>();
+      const c = variable<number>();
 
       const e = expr({ a, b, c })("a + b + c");
       const compiled = compile(e, { a, b, c });
@@ -53,8 +52,8 @@ describe("evaluate 单元测试", () => {
     });
 
     test("undefined 和 null 值", () => {
-      const x = variable(z.union([z.number(), z.null(), z.undefined()]));
-      const y = variable(z.number());
+      const x = variable<number | null | undefined>();
+      const y = variable<number>();
 
       const e = expr({ x, y })("x ?? y");
       const compiled = compile(e, { x, y });

src/evaluate.test.ts

@@ -1,11 +1,10 @@
-import { z } from "zod";
 import type { InferExpressionResult, ValidateExpression } from "./type-parser";
 import type { Expression, Variable } from "./types";
 
 /**
  * 表达式上下文类型约束
  */
-type ExprContext = Record<string, Variable<z.ZodType> | Expression<Record<string, unknown>, unknown>>;
+type ExprContext = Record<string, Variable | Expression<Record<string, unknown>, unknown>>;
 
 /**
  * 表达式错误类型