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+# 索引
+
+<!-- 索引有三列，每列宽度40个字符
++------------------------------------- + ------------------------------------- + ------------
+-->
+
+### P367
+
+```
+TODO
+```
+
+### P368
+
+```
+TODO
+```
+
+### P369
+
+```
+TODO
+```
+
+### P390
+
+```
+TODO
+```
+
+### P391
+
+```
+TODO
+```
+
+### P392
+
+```
+TODO
+```
+
+### P393
+
+```
+TODO
+```
+
+### P394
+
+```
+TODO
+```
+
+### P395
+
+```
+TODO
+```
+
+### P396
+
+```
+TODO
+```
+
+### P397
+
+```
+TODO
+```
+
+### P398
+
+```
+TODO
+```
+
+### P399
+
+```
+TODO
+```
+
+
+### P400
+
+<!-- 索引有三列，每列宽度40个字符
++------------------------------------- + ------------------------------------- + ------------
+-->
+
+```
+  standard 2, 27, 52, 66, 67, 69, 97   variables, shared 257
+unicodepackage 71                      variable-size stack 124
+unicode.IsDigit function 71            variadic function 142, 172
+unicode.IsLetter function 71           vector, bit 165
+unicode.IsLower function 71            vendoring 293
+unicode.IsSpace function 93            visibility 28, 29, 41, 168, 297
+unicode.IsUpper function 71            visit function 122
+unicode/utf8package 69
+unidirectional channel type 230, 231   wait example 130
+union, discriminated 211, 213, 214     WaitForServer function 130
+universe block 46                      walkDir function 247
+Unix domain socket 219                 web
+unmarshaling JSON 110                    crawler 119
+unnamed struct type 163                  crawler, concurrent 239
+unnamed variable 34, 88                  framework 193
+unreachable statement 120              while loop 6
+unsafe package 354                     white-box test 311
+unsafe.AlignOf function 355            Wilkes, Maurice 301
+unsafe.Offsetof function 355           Wirth, Niklaus xiii
+unsafe.Pointer conversion 356          word example 303, 305, 308
+unsafe.Pointer type 356                word example, test of 303
+unsafe.Pointer zero value 356          workspace organization 291
+unsafe.Sizeof function 354             writer lock 266
+unsigned integer 52, 54                writing effective tests 316, 317
+untyped constant types 78
+unused parameter 120                   xkcd JSON interface 113
+URL 123                                XML decoding 213
+URL escape 111                         XML (Extensible Markup Language)
+url.QueryEscape function 111               107
+url.URLtype 193                        (*xml.Decoder).Token method
+url values example 160                     213
+UTF-8 66, 67, 98                       xmlselect example 215
+UTF-8 encodings, table of 67
+utf8.DecodeRuneInString function       zero length slice 87
+    69                                 zero value
+utf8.RuneCountInString function          array 82
+    69                                   boolean 30
+utf8.UTFMaxvalue 98                      channel 225, 246
+                                         func tion 132
+value                                    interface 182
+  addressable   32                       map 95
+  call by 83, 120, 158                   named result 120, 127
+  func tion  132                         number 5, 30
+  interface   181                        pointer 32
+  method 164                             reflect.Value 332
+  utf8.UTFMax 98                         slice 74, 87
+var declaration 5, 30                    string 5, 7, 30
+variable                                 struct 102
+  confinement 261                        unsafe.Pointer 356
+  heap 36
+  http.DefaultClient 253
+  io.Discard 18
+  io.EOF 132
+  lifetime 35, 46, 135
+  local 29, 141
+  os.Args 4
+  stack 36
+  unnamed 34, 88
+variables, escaping 36
+```