Overview
Installation
brew install go
Configuration
Setup default workspace
mkdir ~/go
mkdir ~/go/src
Hello World Example
vi helloworld.go
package main import ( "fmt" ) func main(){ fmt.Println("Hello World") }
Run it
go run helloworld.go
Compile it
go build
Install it
go install
FunctionsÂ
Example showing error return
package main import ( "fmt" "error" "math" ) func main() { result, err := sqrt(16) if err != nil { fmt.Println(err) } else { fmt.Println(result) } } func sqrt(x float64) (float64, error ) { if x < 0 { return 0, errors.New("Undefined for negative numbers") } return math.Sqrt(x), nil }
Structs/Types
package main import ( "fmt" ) type person struct { name string age int } func main(){ p:= person{name: "Jake", age: 23 } fmt.Println(p) }
Commands
Command | Description |
---|---|
go run <src.go> | Run some code |
go build | Compile the code. Outputs to local folder. Executable has folder as name. |
go install | Compiles and places the output in workspace/bin |
go env GOPATH | Outputs the default workspace folder |
Variables
Variables are defined using the following syntax:
var <variablename> <type>
example:
var x int
All variables have a zero value and are pre-initialized to their zero value. For example, an int would have a zero value of 0 and a string would have a zero value of empty string "".
Initializing the variable at declaration time:
var x int = 5
Quick Syntax: infers type based on value.
x:=5
Example:
package main import ( "fmt" ) func main(){ var x int x = 5 fmt.Println(x) }
Structs
References
Reference | URL |
---|---|
Learn Go in 12 Minutes | https://www.youtube.com/watch?v=C8LgvuEBraI |
Go Packages | https://golang.org/pkg/ |
Go By Examples | https://gobyexample.com/ |