go - 如何减少嵌套函数调用中的参数数量

Question

我有一个 go Calltree，其结构如下:

// state is a common struct shared among all "instances" of MyType - simulating member variables for an Interface
(s MyType) Run(state *State){ // called from outside
  // define goroutines that fetch something via http
  HTTPCallback(){ // runs on every http response
    parseData(record, outputChan)
  }
}
(s MyType) parseData(rec []string, outputChan chan(interface{})){
  // doesn't need anything from "state" so far
  doIdMapping(string) 
}


doIdMapping(key) { 
   return state.Map[key] 
}

有没有办法通过 HTTPCallback 和上面所有最终调用 HTTPCallback 的 goroutine 传递“状态”来访问 Map(它是完全不变的)？

这不仅不利于清晰的代码，而且不利于测试。所有中间函数都带有它们甚至不需要依赖的结构指针。我是不是漏掉了 go 的语言设计？ :/

Answer 1

如果所有这些都在一个包中，您可以简单地在包级别声明 State 并在任何地方使用它。例如；

package myHttpClient

import (
    "allthatstuff"
)

state State // not exported but available everywhere in 'myHttpClient'
ExternState State // exported so anyone importing myHttpClient can do myHttpClient.ExternState