From 1c007e46735b29ddec2d1f58e1ad353031a2001f Mon Sep 17 00:00:00 2001 From: chai2010 Date: Mon, 23 Jul 2018 11:37:19 +0800 Subject: [PATCH] =?UTF-8?q?ch1:=20=E6=9B=B4=E6=96=B0=E5=9B=BE=E7=89=87?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ch1-basic/ch1-04-func-method-interface.md | 2 +- ch1-basic/ch1-05-mem.md | 2 +- images/ch1-04-init.ditaa.png | Bin 0 -> 10600 bytes images/ch1-04-init.ditaa.txt | 23 ++++++++++++++++++++++ 4 files changed, 25 insertions(+), 2 deletions(-) create mode 100644 images/ch1-04-init.ditaa.png create mode 100644 images/ch1-04-init.ditaa.txt diff --git a/ch1-basic/ch1-04-func-method-interface.md b/ch1-basic/ch1-04-func-method-interface.md index 1faad33..22ba086 100644 --- a/ch1-basic/ch1-04-func-method-interface.md +++ b/ch1-basic/ch1-04-func-method-interface.md @@ -4,7 +4,7 @@ Go语言程序的初始化和执行总是从`main.main`函数开始的。但是如果`main`包导入了其它的包，则会按照顺序将它们包含进`main`包里（这里的导入顺序依赖具体实现，一般可能是以文件名或包路径名的字符串顺序导入）。如果某个包被多次导入的话，在执行的时候只会导入一次。当一个包被导入时，如果它还导入了其它的包，则先将其它的包包含进来，然后创建和初始化这个包的常量和变量,再调用包里的`init`函数，如果一个包有多个`init`函数的话，调用顺序未定义(实现可能是以文件名的顺序调用)，同一个文件内的多个`init`则是以出现的顺序依次调用（`init`不是普通函数，可以定义有多个，所以也不能被其它函数调用）。最后，当`main`包的所有包级常量、变量被创建和初始化完成，并且`init`函数被执行后，才会进入`main.main`函数，程序开始正常执行。下图是Go程序函数启动顺序的示意图： -![](../images/ch1-04-init.png) +![](../images/ch1-04-init.ditaa.png) 要注意的是，在`main.main`函数执行之前所有代码都运行在同一个goroutine，也就是程序的主系统线程中。因此，如果某个`init`函数内部用go关键字启动了新的goroutine的话，新的goroutine只有在进入`main.main`函数之后才可能被执行到。 diff --git a/ch1-basic/ch1-05-mem.md b/ch1-basic/ch1-05-mem.md index 3356c03..3aa59d5 100644 --- a/ch1-basic/ch1-05-mem.md +++ b/ch1-basic/ch1-05-mem.md @@ -259,7 +259,7 @@ func main() { Go程序的初始化和执行总是从`main.main`函数开始的。但是如果`main`包里导入了其它的包，则会按照顺序将它们包含进`main`包里（这里的导入顺序依赖具体实现，一般可能是以文件名或包路径名的字符串顺序导入）。如果某个包被多次导入的话，在执行的时候只会导入一次。当一个包被导入时，如果它还导入了其它的包，则先将其它的包包含进来，然后创建和初始化这个包的常量和变量。然后就是调用包里的`init`函数，如果一个包有多个`init`函数的话，实现可能是以文件名的顺序调用，同一个文件内的多个`init`则是以出现的顺序依次调用（`init`不是普通函数，可以定义有多个，所以不能被其它函数调用）。最终，在`main`包的所有包常量、包变量被创建和初始化，并且`init`函数被执行后，才会进入`main.main`函数，程序开始正常执行。下图是Go程序函数启动顺序的示意图： -![](../images/ch1-04-init.png) +![](../images/ch1-04-init.ditaa.png) 要注意的是，在`main.main`函数执行之前所有代码都运行在同一个goroutine中，也是运行在程序的主系统线程中。如果某个`init`函数内部用go关键字启动了新的goroutine的话，新的goroutine只有在进入`main.main`函数之后才可能被执行到。 diff --git a/images/ch1-04-init.ditaa.png b/images/ch1-04-init.ditaa.png new file mode 100644 index 0000000000000000000000000000000000000000..8b4bed23f1ba6316a551d805214ae08532253a1e GIT binary patch literal 10600 zcmbVyc_5T++rIJ^X;E1sMLlH;l_kcOHoFKRWE5(YHTx2t3WZYkZSX`WgGpmaw!#oH zC407}vX6b=f9E};((}E4{JyV0WXyeE%efrKd7Rf3a6wafJJVh!Iy$=Tsw(Gn=;-Jr z=;$_}88^aTI=dVyG 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+-=-->| import pkg2 +-=-->| import pkg3 +-=-->| const | + | | | | | | | | | | | | + | : | | : | | : | | : | + | v | | v | | v | | v | + | const |<-\ | const |<-\ | const |<-\ | var | + | | | | | | | | | | | | | | | + | : | | | : | | | : | | | : | + | v | | | v | | | v | | | v | + | var | | | var | | | var | | | init() | + | | | | | | | | | | | | +------+------+ + | : | | | : | | | : | | | + | v | | | v | | | v | \-=-------/ + | init() | | | init() | | | init() | + | | | | | init() | | +------+------+ + | : | | +------+------+ | | + | v | | | \-=-------/ + | main() | \-=-------/ + +-------------+ + +