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如果demo目录下有两个文件 main.go 和mian2.go的话,main.go 和main2.go文件中的package 定义的名字要是同一个
不同的话,是会报错的。
main2.go
main2.go 中的package main2 改为 main就是可以的。
myproject.go
Go code must be kept inside a workspace. A workspace is a directory hierarchy with three directories at its root:
src contains Go source files organized into packages (one package per directory),
pkg contains package objects, and
bin contains executable commands.