renumbering chapters >= 19

24-class-metaprog/evaltime/builderlib.py

@@ -0,0 +1,50 @@
+# tag::BUILDERLIB_TOP[]
+print('@ builderlib module start')
+
+class Builder:  # <1>
+    print('@ Builder body')
+
+    def __init_subclass__(cls):  # <2>
+        print(f'@ Builder.__init_subclass__({cls!r})')
+
+        def inner_0(self):  # <3>
+            print(f'@ SuperA.__init_subclass__:inner_0({self!r})')
+
+        cls.method_a = inner_0
+
+    def __init__(self):
+        super().__init__()
+        print(f'@ Builder.__init__({self!r})')
+
+
+def deco(cls):  # <4>
+    print(f'@ deco({cls!r})')
+
+    def inner_1(self):  # <5>
+        print(f'@ deco:inner_1({self!r})')
+
+    cls.method_b = inner_1
+    return cls  # <6>
+# end::BUILDERLIB_TOP[]
+
+# tag::BUILDERLIB_BOTTOM[]
+class Descriptor:  # <1>
+    print('@ Descriptor body')
+
+    def __init__(self):  # <2>
+        print(f'@ Descriptor.__init__({self!r})')
+
+    def __set_name__(self, owner, name):  # <3>
+        args = (self, owner, name)
+        print(f'@ Descriptor.__set_name__{args!r}')
+
+    def __set__(self, instance, value):  # <4>
+        args = (self, instance, value)
+        print(f'@ Descriptor.__set__{args!r}')
+
+    def __repr__(self):
+        return '<Descriptor instance>'
+
+
+print('@ builderlib module end')
+# end::BUILDERLIB_BOTTOM[]