Golang Block 到底是什么？ 怎么就能解决闭包变量冲突了？

i:=i

golang 官方Effective GOreqreq := req

https://golang.org/doc/effective_go#concurrency

req := reqEffective GO

req

直接这么看，还是有点拗口。不过不重要， 在了解了 golang 的 区块(block) 定义范围之后， 就迎刃而解了。

Blocks

https://golang.org/ref/spec#Blocks

block

Blocks

{}

Block 的范围在哪里？

{}

universe

The universe block encompasses all Go source text.

universe

package

Each package has a package block containing all Go source text for that package.

packagepackagepackage.Variable

file

Each file has a file block containing all Go source text in that file.

block

目前发现现象，

filename_test.gofilename.go

file block

_test

main_test.gomain.gomain.goVarInTest

forifswitch

Each “if”, “for”, and “switch” statement is considered to be in its own implicit block.

forifswitch{}

{}for block(statement block)

i:=istatement block同名变量覆盖

也就是因为 {} 是 for 子block 的原因， for 的 post 可以修改变量 i， 在 statement 中也可以修改变量 i

loop: 0,1,2,9for blockistatement block_iif blockstatement block_ifor blockiloop: 0-9

switch / selectclause

Each clause in a “switch” or “select” statement acts as an implicit block.

switch / selectcase / default:

func blockiswitch clause 分支{