hoanhan101 / go-playground

Collections of Go's programs

go-playground

go-playground is a collection of Go's programs and notes for learning Go, which I mostly use for reference.

Topic

• Basic: scope, callback, function expression, defer, slice, pointer
• Concurrency
• Networking: http, tcp, mux, session, cookie
• Error Handling

Note

How to setup GOPATH

There are 2 essential environment variables to setup before running any Go program:

• GOPATH
• GOROOT

GOPATH is the path to our workspace. It is required and has no default. I'm setting it up at $HOME/go because it works for me.

GOROOT is that path to where Go standard library is located on our local filesystem. Is set automatically setup when we install Go.

Additionally, GOBIN is the path to where our Go binaries are installed from running go install.

All of the environment variables configurations can be set in .bashrc or .zshrc. For example:

export GOPATH=$HOME/go
export PATH=$PATH:/usr/local/go/bin:$GOPATH/bin

Execute the command go env to see all the environment variable.

How to structure project

Exported/unexported, aka visible/not visible

In go we don't say public or or private, we say exported or unexported. Depend on capialization:

• capitalize: exported, visible outside the package
• lowercase: unxported, not visible outside the package

go commands

Assume that our folder directory looks like this:

package
├── main
│  └── main.go
├── utils
│  └── utilOne.go
│  └── utilTwo.go

If we run these commands in our executable, main:

• go run main.go will run the file the file
• go build will make an executable file and put that inside
• go clean will clean that executable file
• go install will make an executable file inside the workspace bin folder and archive file in pkg

If we run these commands in our packages, utils:

• they cannot be run because they are non-main packages
• they cannot be built because there are no executable

go fmt

go fmt ./...: Go fmt all the files in this directory and anything below it.