diff --git a/README.md b/README.md
index 3261c881..44974501 100644
--- a/README.md
+++ b/README.md
@@ -129,8 +129,10 @@ Quick Reference
[Kubernetes](./docs/kubernetes.md)
[LaTeX](./docs/latex.md)
[Laravel 8](./docs/laravel.md)
+[Lua](./docs/lua.md)
[Markdown](./docs/markdown.md)
[MATLAB](./docs/matlab.md)
+[Nix](./docs/nix.md)
[PHP](./docs/php.md)
[R 语言](./docs/r.md)
[Ruby](./docs/ruby.md)
@@ -139,7 +141,6 @@ Quick Reference
[Swift](./docs/swift.md)
[SwiftUI](./docs/swiftui.md)
[Spring Boot](./docs/springboot.md)
-[Lua](./docs/lua.md)
[Minio](./docs/minio.md)
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+
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diff --git a/docs/nix.md b/docs/nix.md
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+Nix 备忘清单
+===
+
+Nix 快速参考备忘单，旨在帮助编写基础的 Nix 代码。Nix 是一个纯函数式包管理器和 NixOS 系统的基础语言。
+
+类型与语法
+---
+
+### 字符串
+
+
+```nix
+let
+ x = "单行字符串";
+ y = ''
+ 多行字符串
+ 支持换行和缩进
+ '';
+ z = ''
+ 前导空格会被自动处理
+ 这行会保持缩进
+ '';
+in
+```
+
+#### 字符串插值
+
+```nix
+let
+ name = "世界";
+ greeting = "你好，${name}！";
+in
+```
+
+#### 转义字符
+
+```nix
+let
+ escaped = ''
+ 引号：\"hello\"，换行：\n，制表符：\t
+ '';
+in
+```
+
+### 整数
+
+```nix
+let
+ x = -123;
+ y = 123;
+ # 支持不同进制
+ hex = 0xFF; # 十六进制: 255
+ bin = 0b1010; # 二进制: 10
+ oct = 0o755; # 八进制: 493
+in
+```
+
+### 浮点数
+
+```nix
+let
+ x = -0.32;
+ y = 0.45;
+ scientific = 1.23e-4; # 科学记数法
+ inf = 1.0 / 0.0; # 无穷大
+in
+```
+
+### 布尔值
+
+```nix
+let
+ x = true;
+ y = false;
+ # 布尔运算
+ and_result = true && false; # false
+ or_result = true || false; # true
+ not_result = !true; # false
+in
+```
+
+### 空值
+
+```nix
+let
+ x = null;
+ # null 表示缺失值
+ # 类似于其他语言的 None 或 undefined
+in
+```
+
+### 路径
+
+```nix
+let
+ absolute = /usr/bin/env; # 绝对路径
+ relative = ./config.nix; # 相对路径
+ home = ~/Documents; # 家目录路径
+ # 路径会在构建时自动复制到 Nix store
+in
+```
+
+### 属性集
+
+
+```nix
+let
+ x = {
+ name = "张三";
+ age = 25;
+ address = {
+ city = "北京";
+ district = "朝阳区";
+ };
+ };
+ y = { c = 3; };
+ # 递归属性集
+ rec_set = rec {
+ x = 1;
+ y = x + 1; # 可以引用同级属性
+ };
+in
+```
+
+参见 [属性集操作](#属性集)
+
+### 列表
+
+
+```nix
+let
+ numbers = [ 1 2 3 4 5 ];
+ mixed = [
+ 1
+ "这是字符串"
+ 23.0
+ null
+ { name = "属性集"; }
+ ];
+ # 列表可以包含任意类型的元素
+ nested = [ [ 1 2 ] [ 3 4 ] ];
+in
+```
+
+### 注释
+
+#### ↓ 单行注释
+
+```nix
+# 这是单行注释
+let x = 1; in x # 行末注释
+```
+
+#### ↓ 多行注释
+
+```nix
+/*
+ 这是多行注释
+ 可以跨越多行
+ /* 可以嵌套 */
+*/
+```
+
+作用域管理
+---
+
+### 定义局部变量
+
+
+```nix
+let
+ x = 1;
+ y = 2;
+ z = x + y; # 可以引用前面定义的变量
+in
+ x + y + z # 返回 6
+```
+
+#### 嵌套 let 表达式
+
+```nix
+let
+ outer = 10;
+in
+ let
+ inner = 5;
+ in
+ outer + inner # 返回 15
+```
+
+### 将变量添加到作用域
+
+```nix
+let
+ x = 1;
+ y = 2;
+in
+ { inherit x y; } # 继承多个变量
+```
+
+#### ↓ 等价于
+
+```nix
+let
+ x = 1;
+ y = 2;
+in
+ { x = x; y = y; }
+```
+
+### 从属性集继承属性
+
+
+```nix
+let
+ config = {
+ host = "localhost";
+ port = 8080;
+ ssl = true;
+ };
+in
+ {
+ inherit (config) host port;
+ # 只继承特定属性
+ }
+```
+
+#### ↓ 等价于
+
+```nix
+let
+ config = {
+ host = "localhost";
+ port = 8080;
+ ssl = true;
+ };
+in
+ {
+ host = config.host;
+ port = config.port;
+ }
+```
+
+### 将所有属性引入作用域
+
+```nix
+let
+ config = {
+ host = "localhost";
+ port = 8080;
+ database = "myapp";
+ };
+in
+ with config;
+ "${host}:${toString port}/${database}" # 返回 "localhost:8080/myapp"
+```
+
+#### 注意事项
+
+```nix
+let
+ x = 1;
+ attrs = { x = 2; y = 3; };
+in
+ with attrs;
+ x + y # x = 1 (局部变量优先级更高), y = 3
+```
+
+条件表达式
+---
+
+### 基本条件表达式
+
+
+```nix
+let
+ x = 10;
+ result = if x > 0
+ then "正数"
+ else if x < 0
+ then "负数"
+ else "零";
+in
+ result
+```
+
+#### 布尔条件判断
+
+```nix
+let
+ isEnabled = true;
+ config = if isEnabled
+ then { port = 8080; debug = true; }
+ else { port = 80; debug = false; };
+in
+ config
+```
+
+#### 字符串条件判断
+
+```nix
+let
+ env = "production";
+ database = if env == "production"
+ then "prod-db.example.com"
+ else if env == "staging"
+ then "staging-db.example.com"
+ else "localhost";
+in
+ database
+```
+
+### 复杂条件判断
+
+
+```nix
+let
+ user = { name = "张三"; age = 25; isAdmin = true; };
+ message = if user.isAdmin && user.age >= 18
+ then "管理员用户: ${user.name}"
+ else "普通用户: ${user.name}";
+in
+ message
+```
+
+### 条件表达式中的属性集
+
+
+```nix
+let
+ env = "production";
+ config = if env == "development"
+ then {
+ debug = true;
+ logLevel = "debug";
+ database.host = "localhost";
+ }
+ else {
+ debug = false;
+ logLevel = "info";
+ database.host = "prod-db.example.com";
+ };
+in
+ config
+```
+
+属性集
+---
+
+### 定义属性集
+
+```nix
+let
+ person = {
+ name = "李四";
+ age = 30;
+ skills = [ "编程" "设计" "管理" ];
+ contact = {
+ email = "lisi@example.com";
+ phone = "138-0000-0000";
+ };
+ };
+in
+ person
+```
+
+### 动态属性名
+
+```nix
+let
+ key = "dynamicKey";
+ attrs = {
+ ${key} = "动态值";
+ "static-key" = "静态值";
+ };
+in
+ attrs # { dynamicKey = "动态值"; static-key = "静态值"; }
+```
+
+### 更新属性集
+
+```nix
+let
+ base = { x = 1; y = 2; };
+ updated = base // { y = 3; z = 4; }; # 合并属性集
+in
+ updated # { x = 1; y = 3; z = 4; }
+```
+
+#### 深度合并
+
+```nix
+let
+ config1 = {
+ server = { host = "localhost"; port = 8080; };
+ database = { name = "test"; };
+ };
+ config2 = {
+ server = { port = 9000; ssl = true; };
+ cache = { enabled = true; };
+ };
+ # 注意：// 操作符只进行浅合并
+ merged = config1 // config2;
+ # server 属性会被完全替换，而不是深度合并
+in
+ merged
+```
+
+### 检查属性是否存在
+
+```nix
+let
+ person = { name = "王五"; age = 28; };
+in
+ {
+ hasName = person ? name; # true
+ hasEmail = person ? email; # false
+ hasNested = person ? contact.email; # false (嵌套检查)
+ }
+```
+
+### 访问属性
+
+```nix
+let
+ config = {
+ server = {
+ host = "localhost";
+ port = 8080;
+ };
+ };
+in
+ {
+ host = config.server.host; # 访问嵌套属性
+ port = config.server.port;
+ }
+```
+
+#### 可选属性访问
+
+```nix
+let
+ config = { server = { host = "localhost"; }; };
+in
+ {
+ port = config.server.port or 3000; # 如果不存在则使用默认值
+ timeout = config.timeout or 30; # 30
+ ssl = config.server.ssl or false; # false
+ }
+```
+
+连接与插值
+---
+
+### 连接列表
+
+```nix
+let
+ list1 = [ 1 2 3 ];
+ list2 = [ 4 5 6 ];
+ combined = list1 ++ list2; # [ 1 2 3 4 5 6 ]
+
+ # 多个列表连接
+ all = [ 0 ] ++ list1 ++ list2 ++ [ 7 8 ];
+in
+ all # [ 0 1 2 3 4 5 6 7 8 ]
+```
+
+### 连接路径与字符串
+
+```nix
+let
+ base = /usr/bin;
+ executable = base + /python3; # /usr/bin/python3
+
+ # 路径与字符串连接
+ config_path = /etc + "/nginx/nginx.conf"; # /etc/nginx/nginx.conf
+
+ # 字符串连接
+ greeting = "你好" + "，世界！"; # "你好，世界！"
+in
+ { inherit executable config_path greeting; }
+```
+
+### 字符串插值
+
+```nix
+let
+ name = "张三";
+ age = 25;
+ score = 95.5;
+in
+ {
+ greeting = "你好，${name}！";
+ info = "姓名：${name}，年龄：${toString age}";
+ result = "考试成绩：${toString score}分";
+
+ # 复杂表达式插值
+ status = "用户 ${name} ${if age >= 18 then "已成年" else "未成年"}";
+
+ # 路径插值
+ config_file = "${./configs}/${name}.conf";
+ }
+```
+
+函数
+---
+
+### 简单函数
+
+```nix
+let
+ # 单参数函数
+ increment = x: x + 1;
+ double = x: x * 2;
+
+ # 使用函数
+ result1 = increment 5; # 6
+ result2 = double 3; # 6
+in
+ { inherit result1 result2; }
+```
+
+### 命名参数
+
+
+```nix
+let
+ # 基本命名参数
+ createUser = {name, age, email}: {
+ inherit name age email;
+ id = builtins.hashString "md5" email;
+ };
+
+ user = createUser {
+ name = "张三";
+ age = 25;
+ email = "zhangsan@example.com";
+ };
+in
+ user
+```
+
+#### 忽略额外参数
+
+```nix
+let
+ # 使用 ... 忽略额外的参数
+ processConfig = {host, port, ...}: {
+ url = "${host}:${toString port}";
+ };
+
+ result = processConfig {
+ host = "localhost";
+ port = 8080;
+ ssl = true; # 会被忽略
+ timeout = 30; # 会被忽略
+ };
+in
+ result # { url = "localhost:8080"; }
+```
+
+#### 默认参数值
+
+```nix
+let
+ # 为参数提供默认值
+ createServer = {
+ host ? "localhost",
+ port ? 8080,
+ ssl ? false
+ }: {
+ inherit host port ssl;
+ url =
+ let proto = if ssl then "https" else "http";
+ in "${proto}://${host}:${toString port}";
+ };
+
+ # 使用所有默认值
+ server1 = createServer {};
+ # 只覆盖 port
+ server2 = createServer {port = 3000;};
+ # 覆盖多个参数
+ server3 = createServer {
+ host = "example.com";
+ port = 443;
+ ssl = true;
+ };
+in
+ { inherit server1 server2 server3; }
+```
+
+#### 绑定到变量
+
+```nix
+let
+ # 将整个参数集绑定到变量，同时解构部分参数
+ logMessage = {
+ level,
+ message,
+ timestamp ? null
+ }@args: {
+ formatted = "[${level}] ${message}";
+ raw = args; # 保留原始参数集
+ hasTimestamp =
+ args ? timestamp && timestamp != null;
+ };
+
+ log = logMessage {
+ level = "INFO";
+ message = "服务器启动成功";
+ user = "admin"; # 额外参数也会保存在 args 中
+ };
+in
+ log
+```
+
+### 多参数函数
+
+```nix
+let
+ # 柯里化函数
+ add = x: y: x + y;
+ multiply = x: y: z: x * y * z;
+
+ # 部分应用
+ add10 = add 10; # 等价于 y: 10 + y
+
+ # 使用示例
+ result1 = add 3 4; # 7
+ result2 = add10 5; # 15
+ result3 = multiply 2 3 4; # 24
+in
+ { inherit result1 result2 result3; }
+```
+
+### 高阶函数
+
+```nix
+let
+ # 接受函数作为参数的高阶函数
+ applyTwice = f: x: f (f x);
+
+ # 返回函数的高阶函数
+ createMultiplier = factor: x: x * factor;
+
+ # 函数组合
+ compose = f: g: x: f (g x);
+
+ # 使用示例
+ double = x: x * 2;
+ increment = x: x + 1;
+
+ result1 = applyTwice double 3; # 12
+ triple = createMultiplier 3;
+ result2 = triple 5; # 15
+ doubleAndIncrement =
+ compose increment double;
+ result3 = doubleAndIncrement 4; # 9
+in
+ { inherit result1 result2 result3; }
+```
+
+### 递归函数
+
+```nix
+let
+ # 计算阶乘
+ factorial = n:
+ if n <= 1
+ then 1
+ else n * factorial (n - 1);
+
+ # 斐波那契数列
+ fibonacci = n:
+ if n <= 1
+ then n
+ else fibonacci (n - 1) + fibonacci (n - 2);
+
+ # 列表长度计算
+ listLength = list:
+ if list == []
+ then 0
+ else 1 + listLength (builtins.tail list);
+
+ # 使用示例
+ fact5 = factorial 5; # 120
+ fib7 = fibonacci 7; # 13
+ len = listLength [1 2 3 4]; # 4
+in
+ { inherit fact5 fib7 len; }
+```
+
+### 条件函数
+
+```nix
+let
+```nix
+let
+ # 根据条件选择不同的处理函数
+ processData = condition: data:
+ let
+ uppercaseProcessor = str:
+ builtins.replaceStrings
+ ["a" "e" "i" "o" "u"]
+ ["A" "E" "I" "O" "U"] str;
+
+ lengthProcessor = str:
+ toString (builtins.stringLength str);
+
+ reverseProcessor = str:
+ let
+ len = builtins.stringLength str;
+ chars = builtins.genList
+ (i: builtins.substring
+ (len - 1 - i) 1 str) len;
+ in
+ builtins.concatStringsSep "" chars;
+ in
+ if condition == "uppercase"
+ then uppercaseProcessor data
+ else if condition == "length"
+ then lengthProcessor data
+ else if condition == "reverse"
+ then reverseProcessor data
+ else data;
+
+ # 使用示例
+ text = "hello world";
+ result1 = processData "uppercase" text;
+ result2 = processData "length" text;
+ result3 = processData "reverse" text;
+in
+ { inherit result1 result2 result3; }
+```
+
+### 函数工厂
+
+```nix
+let
+ # 创建验证器函数的工厂
+ createValidator = rules: value:
+ let
+ checkRule = rule:
+ if rule.type == "minLength"
+ then
+ builtins.stringLength value >= rule.value
+ else if rule.type == "maxLength"
+ then
+ builtins.stringLength value <= rule.value
+ else if rule.type == "contains"
+ then
+ builtins.match ".*${rule.value}.*" value
+ != null
+ else true;
+
+ results = map checkRule rules;
+ allValid = builtins.all (x: x) results;
+ in
+ {
+ valid = allValid;
+ value = value;
+ errors = builtins.filter
+ (rule: !checkRule rule) rules;
+ };
+
+ # 创建特定的验证器
+ emailValidator = createValidator [
+ { type = "minLength"; value = 5; }
+ { type = "contains"; value = "@"; }
+ { type = "contains"; value = "."; }
+ ];
+
+ passwordValidator = createValidator [
+ { type = "minLength"; value = 8; }
+ { type = "maxLength"; value = 32; }
+ ];
+
+ # 使用示例
+ email_result = emailValidator "user@example.com";
+ password_result = passwordValidator "mypassword123";
+in
+ { inherit email_result password_result; }
+```
+
+### 函数式编程工具
+
+```nix
+let
+ # 映射函数
+ mapList = f: list:
+ if list == []
+ then []
+ else
+ let head = f (builtins.head list);
+ tail = mapList f (builtins.tail list);
+ in [ head ] ++ tail;
+
+ # 过滤函数
+ filterList = predicate: list:
+ if list == []
+ then []
+ else
+ let
+ head = builtins.head list;
+ tail = builtins.tail list;
+ filtered_tail =
+ filterList predicate tail;
+ in
+ if predicate head
+ then [ head ] ++ filtered_tail
+ else filtered_tail;
+
+ # 归约函数
+ reduceList = f: initial: list:
+ if list == []
+ then initial
+ else
+ let head = builtins.head list;
+ tail = builtins.tail list;
+ in reduceList f (f initial head) tail;
+
+ # 使用示例
+ numbers = [ 1 2 3 4 5 ];
+ doubled = mapList (x: x * 2) numbers;
+ evens = filterList (x: x mod 2 == 0) numbers;
+ sum = reduceList (acc: x: acc + x) 0 numbers;
+ product = reduceList (acc: x: acc * x) 1 numbers;
+in
+ { inherit doubled evens sum product; }
+```
+
+内置函数
+---
+
+### 类型检查函数
+
+```nix
+let
+ value = "hello";
+in
+ {
+ isString = builtins.isString value;
+ # true
+ isInt = builtins.isInt value;
+ # false
+ isBool = builtins.isBool true;
+ # true
+ isList = builtins.isList [1 2 3];
+ # true
+ isAttrs = builtins.isAttrs {x = 1;};
+ # true
+ isFunction = builtins.isFunction (x: x);
+ # true
+ }
+```
+
+### 字符串操作函数
+
+
+```nix
+let
+ text = "Hello, Nix World!";
+in
+ {
+ length = builtins.stringLength text; # 18
+ substring = builtins.substring 7 3 text; # "Nix"
+ split = builtins.split " " text; # 分割字符串
+ replace = builtins.replaceStrings ["Nix"] ["世界"] text; # "Hello, 世界 World!"
+
+ # 大小写转换需要自定义实现
+ toLower = builtins.replaceStrings
+ ["A" "B" "C" "D" "E" "F" "G" "H" "I" "J" "K" "L" "M"
+ "N" "O" "P" "Q" "R" "S" "T" "U" "V" "W" "X" "Y" "Z"]
+ ["a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m"
+ "n" "o" "p" "q" "r" "s" "t" "u" "v" "w" "x" "y" "z"]
+ "HELLO";
+ }
+```
+
+### 列表操作函数
+
+```nix
+let
+ numbers = [1 2 3 4 5];
+ strings = ["apple" "banana" "cherry"];
+in
+ {
+ length = builtins.length numbers; # 5
+ head = builtins.head numbers; # 1
+ tail = builtins.tail numbers; # [2 3 4 5]
+
+ # 映射函数
+ doubled = map (x: x * 2) numbers; # [2 4 6 8 10]
+ # 过滤函数
+ evens = builtins.filter (x: x mod 2 == 0) numbers; # [2 4]
+ # 折叠函数
+ sum = builtins.foldl' (acc: x: acc + x) 0 numbers; # 15
+ # 元素查找
+ hasThree = builtins.elem 3 numbers; # true
+ # 排序
+ sorted = builtins.sort (a: b: a < b) [3 1 4 1 5 9]; # [1 1 3 4 5 9]
+ }
+```
+
+### 属性集操作函数
+
+
+```nix
+let
+ attrs = { a = 1; b = 2; c = 3; };
+in
+ {
+ keys = builtins.attrNames attrs; # ["a" "b" "c"]
+ values = builtins.attrValues attrs; # [1 2 3]
+ hasAttr = builtins.hasAttr "b" attrs; # true
+
+ # 映射属性值
+ doubled = builtins.mapAttrs (name: value: value * 2) attrs;
+ # { a = 2; b = 4; c = 6; }
+
+ # 过滤属性
+ filtered = builtins.filterAttrs (name: value: value > 1) attrs;
+ # { b = 2; c = 3; }
+
+ # 移除属性
+ removed = builtins.removeAttrs attrs ["b"]; # { a = 1; c = 3; }
+ }
+```
+
+导入与模块
+---
+
+### 导入文件
+
+```nix
+let
+ # 导入其他 Nix 文件
+ utils = import ./utils.nix;
+ config = import ./config.nix;
+
+ # 带参数导入
+ lib = import ;
+
+ # 导入并传递参数
+ myModule = import ./module.nix {
+ pkgs = import {};
+ config = { enableFeature = true; };
+ };
+in
+ {
+ inherit utils config lib myModule;
+ }
+```
+
+### 模块定义
+
+
+```nix
+# module.nix 示例
+{ pkgs, config, ... }:
+
+{
+ # 模块选项
+ options = {
+ services.myapp = {
+ enable = lib.mkOption {
+ type = lib.types.bool;
+ default = false;
+ description = "启用 MyApp 服务";
+ };
+
+ port = lib.mkOption {
+ type = lib.types.int;
+ default = 8080;
+ description = "MyApp 监听端口";
+ };
+ };
+ };
+
+ # 模块配置
+ config = lib.mkIf config.services.myapp.enable {
+ systemd.services.myapp = {
+ description = "MyApp 服务";
+ after = ["network.target"];
+ serviceConfig = {
+ ExecStart = "${pkgs.myapp}/bin/myapp --port ${toString config.services.myapp.port}";
+ Restart = "always";
+ };
+ };
+ };
+}
+```
+
+包管理
+---
+
+### 基本包定义
+
+```nix
+# default.nix 或 shell.nix
+{ pkgs ? import {} }:
+
+pkgs.stdenv.mkDerivation {
+ pname = "my-app";
+ version = "1.0.0";
+
+ src = ./.; # 当前目录作为源码
+
+ buildInputs = with pkgs; [
+ nodejs
+ yarn
+ ];
+
+ buildPhase = ''
+ yarn install
+ yarn build
+ '';
+
+ installPhase = ''
+ mkdir -p $out/bin
+ cp -r dist/* $out/
+ makeWrapper ${pkgs.nodejs}/bin/node $out/bin/my-app \
+ --add-flags "$out/index.js"
+ '';
+
+ meta = with pkgs.lib; {
+ description = "我的应用程序";
+ homepage = "https://example.com";
+ license = licenses.mit;
+ maintainers = with maintainers; [ "your-name" ];
+ };
+}
+```
+
+### 开发环境
+
+
+```nix
+# shell.nix
+{ pkgs ? import {} }:
+
+pkgs.mkShell {
+ buildInputs = with pkgs; [
+ # 开发工具
+ git
+ nodejs
+ yarn
+ python3
+
+ # 系统库
+ pkg-config
+ openssl
+
+ # 数据库
+ postgresql
+ redis
+ ];
+
+ # 环境变量
+ shellHook = ''
+ echo "欢迎进入开发环境！"
+ export DATABASE_URL="postgresql://localhost/myapp"
+ export REDIS_URL="redis://localhost:6379"
+
+ # 自动启动服务
+ if ! pgrep -f "postgres" > /dev/null; then
+ echo "启动 PostgreSQL..."
+ postgres -D $HOME/postgres-data &
+ fi
+ '';
+}
+```
+
+常用工具函数
+---
+
+### 递归函数
+
+
+```nix
+let
+ # 计算阶乘
+ factorial = n:
+ if n <= 1
+ then 1
+ else n * factorial (n - 1);
+
+ # 列表求和
+ sumList = list:
+ if list == []
+ then 0
+ else builtins.head list + sumList (builtins.tail list);
+
+ # 深度合并属性集
+ deepMerge = a: b:
+ let
+ mergeAttr = name:
+ let
+ aVal = a.${name};
+ bVal = b.${name};
+ in
+ if builtins.isAttrs aVal && builtins.isAttrs bVal
+ then deepMerge aVal bVal
+ else bVal;
+ in
+ a // b // builtins.listToAttrs (
+ map (name: { inherit name; value = mergeAttr name; })
+ (builtins.filter (name: builtins.hasAttr name a) (builtins.attrNames b))
+ );
+in
+ {
+ fact5 = factorial 5; # 120
+ listSum = sumList [1 2 3 4 5]; # 15
+ merged = deepMerge
+ { a = { x = 1; y = 2; }; c = 3; }
+ { a = { y = 9; z = 4; }; d = 5; };
+ }
+```
+
+错误处理
+---
+
+### 断言
+
+```nix
+let
+ version = "1.2.3";
+
+ # 基本断言
+ validVersion = assert builtins.stringLength version > 0; version;
+
+ # 带消息的断言（通过 throw 实现）
+ checkPort = port:
+ if port < 1 || port > 65535
+ then throw "端口号必须在 1-65535 之间，当前值: ${toString port}"
+ else port;
+
+ # 条件检查
+ config = {
+ port = checkPort 8080;
+ host = if builtins.getEnv "HOST" != ""
+ then builtins.getEnv "HOST"
+ else "localhost";
+ };
+in
+ config
+```
+
+### 异常处理
+
+
+```nix
+let
+ # 安全的属性访问
+ safeGet = attrs: path: default:
+ let
+ keys = builtins.split "\\." path;
+ getValue = obj: keyList:
+ if keyList == [] then obj
+ else if !builtins.isAttrs obj then default
+ else if !builtins.hasAttr (builtins.head keyList) obj then default
+ else getValue (obj.${builtins.head keyList}) (builtins.tail keyList);
+ in
+ getValue attrs keys;
+
+ config = {
+ database = {
+ host = "localhost";
+ port = 5432;
+ };
+ };
+
+ # 安全访问嵌套属性
+ dbHost = safeGet config "database.host" "default-host"; # "localhost"
+ dbUser = safeGet config "database.user" "default-user"; # "default-user"
+in
+ { inherit dbHost dbUser; }
+```
+
+来源
+---
+
+- [Nix 手册](https://nixos.org/manual/nix/stable/) - 官方用户手册
+- [NixOS 手册](https://nixos.org/manual/nixos/stable/) - NixOS 系统配置指南
+- [Nixpkgs 手册](https://nixos.org/manual/nixpkgs/stable/) - 包管理指南
+- [NixOS/nixpkgs](https://github.com/NixOS/nixpkgs) - 官方包仓库
+- [NixOS/nix](https://github.com/NixOS/nix) - Nix 包管理器源码
+- [Nix Pills](https://nixos.org/guides/nix-pills/) - 深入学习 Nix 的教程
+- [nix-shell](https://nixos.org/manual/nix/stable/command-ref/nix-shell.html) - 创建开发环境
+- [nix-build](https://nixos.org/manual/nix/stable/command-ref/nix-build.html) - 构建包
+- [nix-env](https://nixos.org/manual/nix/stable/command-ref/nix-env.html) - 用户环境管理
+- [nixos-rebuild](https://nixos.org/manual/nixos/stable/administration/administration.html) - 系统重构建
+- [NixOS/marketing](https://github.com/nixos/marketing) _(github.com)_
+- [Nix 语言官方文档](https://nixos.org/manual/nix/stable/expressions/language-values.html) _(nixos.org)_