GO111MODULE = “off”

If GO111MODULE=”off” and the code is not in GOPATH/ SRC, then main.go is not in GOPATH/ SRC. That is, the following main.go is not in the GOPATH/ SRC directory, and I want to use content from another module that is not in the standard library or GOROOT (we don’t normally modify GOROOT).

An error occurs when running the code

main.go:4:2: cannot find package "module" in any of:
    /usr/local/go/src/module (from $GOROOT)
    /home/linux/go/src/module (from $GOPATH)
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Solution set GOPATH

Go env -w GOPATH=~/test # Set this to ~/test because I need to write code under ~/test/ SRCCopy the code

Then write in the $GOPATH/ SRC directory

The go compiler looks for modules under $GOPATH/ SRC. Each directory under SRC can be a module, and a directory in a directory can be a module if we need to access modules in a directory within a directory, as shown in the following figure

We need to call the moduleA module in module, just use

import "module/moduleA"
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GO111MODULE = “on”

With GO111MODULE=”on”, we call the written module directly, as shown below

An error is reported directly

main.go:4:2: package module is not in GOROOT (/usr/local/go/src/module)
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The solution

  1. First: set GO111MODULE=”off” and then set GOPATH as above
  2. The second way: use the Go mod as follows

First we need to initialize a go.mod using

Go mod init test # Test can be any nameCopy the code

Then we import the module, starting with test(defined at initialization), followed by the module path, for example

import "test/module"
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If Goland returns an error this way, but it compiles normally, delete the.idea directory in the current directory and restart the project

The same is true if we want to reference nested modules

import "test/module/moduleA"
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