Go tools

go help
go help get

go env
go env GOPATH

go doc filepath.Glob

Install go

/usr/local/go           # installation dir
/usr/local/go/bin/go    # binary location

wget -c https://go.dev/dl/go1.25.6.linux-amd64.tar.gz
sudo rm -rf /usr/local/go && sudo tar -C /usr/local -xzf go1.25.6.linux-amd64.tar.gz
go version

# in ~/.bashrc

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

# update to go1.25.6
go env -w GOTOOLCHAIN=go1.25.6+auto

sudo rm -fr /usr/local/go
# then remove go from $PATH

gopls

sudo apt remove gopls
go install golang.org/x/tools/gopls@latest
which gopls
gopls version

goimports

go install golang.org/x/tools/cmd/goimports@latest
goimports -w file.go

Start / run a program

go mod init myproject/example
go mod tidy

go help mod
	go mod <command> [arguments]
The commands are:
	download    download modules to local cache
	edit        edit go.mod from tools or scripts
	graph       print module requirement graph
	init        initialize new module in current directory
	tidy        add missing and remove unused modules
	vendor      make vendored copy of dependencies
	verify      verify dependencies have expected content
	why         explain why packages or modules are needed

vi main.go

package main

import "fmt"

func main() {
    fmt.Println("Hello, world.")
}

# ?????
go install example/user/hello

# compile and run
go run main.go

# build en executable and execute it
go build main.go && ./main

gofmt

go doc cmd/gofmt

# recursively gofmt files overwrite and print names of overwritten files
gofmt -l -w .

gofmt -w file.go

gofmt <filename or directory>
gofmt -w file.go    # overwrite file.go
gofmt -d file.go    # print the diff
gofmt -l *.go       # list the file names that differ
    -comments=true      # Print comments; if false, all comments are elided from the output.
    -tabs=true          # Indent with tabs; if false, spaces are used instead.
    -tabwidth=8         # Tab width in spaces.

gofmt [flags] [path ...]

The flags are:
    -d
    	Do not print reformatted sources to standard output.
    	If a file's formatting is different than gofmt's, print diffs
    	to standard output.
    -e
    	Print all (including spurious) errors.
    -l
    	Do not print reformatted sources to standard output.
    	If a file's formatting is different from gofmt's, print its name
    	to standard output.
    -r rule
    	Apply the rewrite rule to the source before reformatting.
    -s
    	Try to simplify code (after applying the rewrite rule, if any).
    -w
    	Do not print reformatted sources to standard output.
    	If a file's formatting is different from gofmt's, overwrite it
    	with gofmt's version. If an error occurred during overwriting,
    	the original file is restored from an automatic backup.

air

• https://github.com/cosmtrek/air
• Reference config: https://github.com/cosmtrek/air/blob/master/air_example.toml

curl -sSfL https://raw.githubusercontent.com/cosmtrek/air/master/install.sh | sh -s -- -b $(go env GOPATH)/bin

# cd /path/to/project/src
air init    # creates .air.toml
air         # runs the application using .air.toml

# in file .gitignore
src/tmp