新增「类型对象与自定义类」章节，收尾第二部分内建对象

Prodesire · Prodesire · commit 4dd858c63624 · 2026-06-23T13:24:18.000+08:00
覆盖实例创建、类创建、属性查找优先级、MRO 与 C3 线性化、描述符、__slots__、元类，并配 5 张图
diff --git a/.vitepress/config.mts b/.vitepress/config.mts
@@ -56,7 +56,8 @@ export default defineConfig({
           { text: 'Python 元组对象', link: '/objects/tuple-object/' },
           { text: 'Python 字典对象', link: '/objects/dict-object/' },
           { text: 'Python 集合对象', link: '/objects/set-object/' },
-          { text: 'Python 布尔与 None 对象', link: '/objects/bool-none-object/' }
+          { text: 'Python 布尔与 None 对象', link: '/objects/bool-none-object/' },
+          { text: 'Python 类型对象与自定义类', link: '/objects/type-object/' }
         ]
       },
       {
diff --git a/SUMMARY.md b/SUMMARY.md
@@ -20,5 +20,6 @@
 - [Python Dict 对象](objects/dict-object/index.md)
 - [Python Set 对象](objects/set-object/index.md)
 - [Python 布尔与 None 对象](objects/bool-none-object/index.md)
+- [Python 类型对象与自定义类](objects/type-object/index.md)
 
 ## 第 3 部分：Python 虚拟机
diff --git a/index.md b/index.md
@@ -15,7 +15,7 @@
     - [x] Windows 环境下编译 Python
     - [x] UNIX/Linux 环境下编译 Python
     - [x] 修改 Python 源码
-- [ ] Python 内建对象
+- [x] Python 内建对象
     - [x] Python 对象初探
     - [x] Python 整数对象
     - [x] Python 浮点数对象
@@ -26,6 +26,7 @@
     - [x] Python 字典对象
     - [x] Python 集合对象
     - [x] Python 布尔与 None 对象
+    - [x] Python 类型对象与自定义类
 - [ ] Python 虚拟机
     - [ ] Python 编译结果
     - [ ] Python 虚拟机框架
diff --git a/objects/type-object/attr-lookup.svg b/objects/type-object/attr-lookup.svg
@@ -0,0 +1,50 @@
+<svg width="100%" viewBox="0 0 640 320" xmlns="http://www.w3.org/2000/svg" role="img" font-family="-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'PingFang SC','Microsoft YaHei',sans-serif">
+<title>obj.attr 的属性查找顺序</title>
+<desc>访问 obj.attr 时，_PyObject_GenericGetAttrWithDict 按优先级查找：① 先在类型的 MRO 里找数据描述符（同时有 __get__ 和 __set__），命中则调用其 __get__ 返回；② 否则查实例自己的 __dict__；③ 否则用类 MRO 里找到的非数据描述符（如方法）或类属性；④ 都没有则抛 AttributeError。</desc>
+<defs>
+  <style>
+    .ti{font-size:13px;font-weight:600;}
+    .b{font-size:11.5px;font-weight:600;}
+    .s{font-size:10.5px;}
+    .lab{font-size:10.5px;}
+  </style>
+  <filter id="sh" x="-30%" y="-30%" width="160%" height="160%"><feDropShadow dx="0" dy="1.4" stdDeviation="2" flood-color="#2A2A28" flood-opacity="0.12"/></filter>
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+  <marker id="ah" viewBox="0 0 10 10" refX="8" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M2 1L8 5L2 9" fill="none" stroke="#8E8B80" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"/></marker>
+  <marker id="ahg" viewBox="0 0 10 10" refX="8" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path d="M2 1L8 5L2 9" fill="none" stroke="#1E8B6F" stroke-width="1.6" stroke-linecap="round" stroke-linejoin="round"/></marker>
+</defs>
+
+<rect x="0" y="0" width="640" height="320" fill="#FBFAF6"/>
+<text x="240" y="28" text-anchor="middle" class="ti" fill="#33322E">obj.attr 的查找顺序（优先级从上到下）</text>
+
+<!-- box1 -->
+<rect x="80" y="44" width="332" height="46" rx="10" fill="url(#gP)" stroke="#CCC7F1" stroke-width="1" filter="url(#sh)"/>
+<text x="96" y="65" class="b" fill="#2E2972">① 数据描述符（类的 MRO 中）</text>
+<text x="96" y="82" class="s" fill="#4A4396">同时有 __get__ 和 __set__，优先级最高</text>
+<!-- box2 -->
+<rect x="80" y="118" width="332" height="46" rx="10" fill="url(#gG)" stroke="#A8DCC9" stroke-width="1" filter="url(#sh)"/>
+<text x="96" y="139" class="b" fill="#0A463A">② 实例自己的 __dict__</text>
+<text x="96" y="156" class="s" fill="#0C5945">对象上 self.x = ... 设的属性</text>
+<!-- box3 -->
+<rect x="80" y="192" width="332" height="46" rx="10" fill="url(#gB)" stroke="#C3D2E8" stroke-width="1" filter="url(#sh)"/>
+<text x="96" y="213" class="b" fill="#28415F">③ 非数据描述符 / 类属性（类 MRO）</text>
+<text x="96" y="230" class="s" fill="#4A5E80">方法（只有 __get__）、类变量等</text>
+<!-- box4 -->
+<rect x="80" y="266" width="332" height="40" rx="10" fill="url(#gR)" stroke="#E0C6C6" stroke-width="1" filter="url(#sh)"/>
+<text x="96" y="291" class="b" fill="#5C3030">④ 都没有 → 抛 AttributeError</text>
+
+<!-- down arrows (miss) -->
+<g fill="none" stroke="#8E8B80" stroke-width="1.5" marker-end="url(#ah)">
+  <path d="M246,90 V116"/><path d="M246,164 V190"/><path d="M246,238 V264"/>
+</g>
+<g class="lab" fill="#9A988F"><text x="256" y="108">未命中 ↓</text><text x="256" y="182">未命中 ↓</text><text x="256" y="256">未命中 ↓</text></g>
+
+<!-- hit -> return -->
+<g fill="none" stroke="#1E8B6F" stroke-width="1.6" marker-end="url(#ahg)">
+  <path d="M412,67 H470"/><path d="M412,141 H470"/><path d="M412,215 H470"/>
+</g>
+<g class="lab" fill="#1E8B6F"><text x="476" y="64">命中</text><text x="476" y="79">→ 返回</text><text x="476" y="138">命中→返回</text><text x="476" y="212">命中→返回</text></g>
+</svg>
diff --git a/objects/type-object/class-creation.svg b/objects/type-object/class-creation.svg
@@ -0,0 +1,37 @@
+<svg width="100%" viewBox="0 0 700 180" xmlns="http://www.w3.org/2000/svg" role="img" font-family="-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'PingFang SC','Microsoft YaHei',sans-serif">
+<title>类的创建：class 语句 → type(name, bases, namespace)</title>
+<desc>class 语句会被编译成对 __build_class__ 的调用：先执行类体得到一个命名空间字典，再调用元类（默认是 type）以 type(name, bases, namespace) 创建类型对象。所以「类」本身就是 type 的实例。</desc>
+<defs>
+  <style>
+    .ti{font-size:12.5px;font-weight:600;}
+    .b{font-size:11.5px;font-weight:600;}
+    .c{font-size:10.5px;font-family:'SF Mono','JetBrains Mono',ui-monospace,Consolas,monospace;}
+    .s{font-size:10px;}
+  </style>
+  <filter id="sh" x="-30%" y="-30%" width="160%" height="160%"><feDropShadow dx="0" dy="1.4" stdDeviation="2" flood-color="#2A2A28" flood-opacity="0.12"/></filter>
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+</defs>
+
+<rect x="0" y="0" width="700" height="180" fill="#FBFAF6"/>
+<text x="350" y="30" text-anchor="middle" class="ti" fill="#2E2972">class 语句背后：调用元类 type(name, bases, namespace) 造类</text>
+
+<g fill="none" stroke="#8E8B80" stroke-width="1.6" marker-end="url(#ah)">
+  <path d="M186,96 H214"/><path d="M408,96 H436"/>
+</g>
+
+<rect x="24" y="64" width="162" height="64" rx="9" fill="url(#gN)" stroke="#D8D3C6" stroke-width="1" filter="url(#sh)"/>
+<text x="105" y="90" text-anchor="middle" class="c" fill="#33322E">class Foo(Base):</text>
+<text x="105" y="106" text-anchor="middle" class="c" fill="#33322E">    x = 1</text>
+<text x="105" y="120" text-anchor="middle" class="s" fill="#7B7A72">（类体 → 命名空间字典）</text>
+
+<rect x="216" y="64" width="192" height="64" rx="9" fill="url(#gP)" stroke="#CCC7F1" stroke-width="1" filter="url(#sh)"/>
+<text x="312" y="90" text-anchor="middle" class="b" fill="#2E2972">type(name, bases, namespace)</text>
+<text x="312" y="108" text-anchor="middle" class="s" fill="#4A4396">__build_class__ 调用元类（默认 type）</text>
+<text x="312" y="122" text-anchor="middle" class="s" fill="#4A4396">→ type_new 创建类型对象</text>
+
+<rect x="438" y="64" width="238" height="64" rx="9" fill="#FFFFFF" stroke="#CCC7F1" stroke-width="1.1" filter="url(#sh)"/>
+<text x="557" y="92" text-anchor="middle" class="b" fill="#2E2972">类型对象 Foo</text>
+<text x="557" y="112" text-anchor="middle" class="s" fill="#4A4396">它本身是 type 的实例（type(Foo) is type）</text>
+</svg>
diff --git a/objects/type-object/descriptor.svg b/objects/type-object/descriptor.svg
@@ -0,0 +1,39 @@
+<svg width="100%" viewBox="0 0 660 220" xmlns="http://www.w3.org/2000/svg" role="img" font-family="-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'PingFang SC','Microsoft YaHei',sans-serif">
+<title>方法是描述符：访问时绑定 self</title>
+<desc>类里定义的函数是非数据描述符（只有 __get__）。在实例上访问 p.m 时，触发 func_descr_get，返回一个把函数和实例绑定起来的「绑定方法」（自动带上 self=p）；在类上访问 P.m 时则返回函数本身。这就是方法能拿到 self 的原因。</desc>
+<defs>
+  <style>
+    .ti{font-size:12.5px;font-weight:600;}
+    .b{font-size:11.5px;font-weight:600;}
+    .c{font-size:11px;font-family:'SF Mono','JetBrains Mono',ui-monospace,Consolas,monospace;}
+    .s{font-size:10.5px;}
+  </style>
+  <filter id="sh" x="-30%" y="-30%" width="160%" height="160%"><feDropShadow dx="0" dy="1.4" stdDeviation="2" flood-color="#2A2A28" flood-opacity="0.12"/></filter>
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+</defs>
+
+<rect x="0" y="0" width="660" height="220" fill="#FBFAF6"/>
+<text x="330" y="28" text-anchor="middle" class="ti" fill="#28415F">方法是描述符：实例上访问时绑定 self</text>
+
+<!-- center: function in class -->
+<rect x="246" y="52" width="168" height="44" rx="9" fill="url(#gN)" stroke="#D8D3C6" stroke-width="1" filter="url(#sh)"/>
+<text x="330" y="72" text-anchor="middle" class="b" fill="#33322E">类 P 里的函数 m</text>
+<text x="330" y="88" text-anchor="middle" class="s" fill="#7B7A72">非数据描述符（只有 __get__）</text>
+
+<!-- left: instance access -->
+<path d="M256,96 C200,116 170,128 150,144" fill="none" stroke="#8E8B80" stroke-width="1.5" marker-end="url(#ah)"/>
+<text x="170" y="120" class="c" fill="#46453F">p.m（实例）</text>
+<rect x="40" y="148" width="240" height="52" rx="9" fill="url(#gG)" stroke="#A8DCC9" stroke-width="1" filter="url(#sh)"/>
+<text x="160" y="170" text-anchor="middle" class="b" fill="#0A463A">func.__get__(p, P) → 绑定方法</text>
+<text x="160" y="188" text-anchor="middle" class="s" fill="#0C5945">自动带上 self = p（即 PyMethod_New）</text>
+
+<!-- right: class access -->
+<path d="M404,96 C460,116 490,128 510,144" fill="none" stroke="#8E8B80" stroke-width="1.5" marker-end="url(#ah)"/>
+<text x="430" y="120" class="c" fill="#46453F">P.m（类）</text>
+<rect x="380" y="148" width="240" height="52" rx="9" fill="url(#gB)" stroke="#C3D2E8" stroke-width="1" filter="url(#sh)"/>
+<text x="500" y="170" text-anchor="middle" class="b" fill="#28415F">函数 m 本身</text>
+<text x="500" y="188" text-anchor="middle" class="s" fill="#4A5E80">不绑定（obj 为 None）</text>
+</svg>
diff --git a/objects/type-object/index.md b/objects/type-object/index.md
diff --git a/objects/type-object/instance-creation.svg b/objects/type-object/instance-creation.svg
diff --git a/objects/type-object/mro.svg b/objects/type-object/mro.svg

Original file line number	Diff line number	Diff line change
`@@ -56,7 +56,8 @@ export default defineConfig({`
`56`	`56`	`{ text: 'Python 元组对象', link: '/objects/tuple-object/' },`
`57`	`57`	`{ text: 'Python 字典对象', link: '/objects/dict-object/' },`
`58`	`58`	`{ text: 'Python 集合对象', link: '/objects/set-object/' },`
`59`		`- { text: 'Python 布尔与 None 对象', link: '/objects/bool-none-object/' }`
	`59`	`+ { text: 'Python 布尔与 None 对象', link: '/objects/bool-none-object/' },`
	`60`	`+ { text: 'Python 类型对象与自定义类', link: '/objects/type-object/' }`
`60`	`61`	`]`
`61`	`62`	`},`
`62`	`63`	`{`