Now that we know how to declare & use Go packages, let’s look through the rest of the code:
func main () { fmt.Println("Hello World") }
main
Function
We use the func
keyword to declare the Go function main
:
- The
func
keyword denotes the start of a function declaration. func
is followed by the name of the function:main
.- After the name there follows a pair of parentheses
()
and a set of curly braces{}
. - The function code is written inside the set of curly braces.
Function Code
The code inside a function is indented. The code here invokes the Println
function in the fmt
package (that we imported earlier) to print the message "Hello World"
.
Invoking Functions
Normally when we write functions, you need to write code to invoke them, otherwise they are unused. However, the main
function is different if it resides in the main
package.
When we have a main
function in the main
package, this is special to Go. When compiled, an executable is produced, and when run, the executable uses the main
function as the starting point.
Instructions
Let’s define our function using the func
keyword, followed by the name main
, a set of empty parentheses ()
, and a set of curly braces {}
.
Inside the set of curly braces, add a new line and insert:
fmt.Println("Hello World")
Then make sure the closing brace }
is also on its own line.
You can also change the Hello World
portion to whatever you want, after all it’s your program!
Run main.go in the terminal to see our output!