Summary of Golang Syntax (iii): Visibility rules (public and private, access rights)

This is a creation in Article, where the information may have evolved or changed.     The go language does not have public, protected, private, and other access control modifiers like other languages, which control visibility by letter capitalization, if defined constants, variables, types, interfaces, structures, The name of a function, such as the beginning of a capital letter, means that it can be accessed or invoked by another package (equivalent to public), and the non-uppercase start can only be used within the package (the equivalent of private, variable or constant can also start with an underscore)
For example:
Visibility/test.go

package visibility import "fmt" const PI = 3.145const pi = 3.14const _PI = 3.14 var P int = 1var p int = 1 func private_function() {fmt.Println("only used in this package!")} func Public_fuction() {fmt.Println("used in anywhere!")}

Main.go

package main import ("visibility""fmt") func main() {visibility.Public_fuction() //used in anywhere!  //visibility.private_function ()//cannot access private functions and cannot be compiled by  fmt   println   ( visibility   p  )    Span class= "com" style= "Color:rgb (147,161,161)" >//1    //fmt. PRINTLN (VISIBILITY.P)//cannot access private variables and cannot be compiled by  fmt   println   ( visibility   pi  )    Span class= "com" style= "Color:rgb (147,161,161)" >//3.14  //fmt.Println(visibility.pi) //不能访问私有常量，无法通过编译//fmt.Println(visibility._PI) //不能访问私有常量，无法通过编译}