Go 句法

Go 语法

A Go file consists of the following parts:

• Package declaration
• Import packages
• Functions
• Statements and expressions

Look at the following code, to understand it better:

示例解释

Line 1: In Go, every program is part of a package. We define this using the package keyword. In this example, the program belongs to the main package.

Line 2: import ("fmt") lets us import files included in the fmt package.

Line 3: A blank line. Go ignores white space. Having white spaces in code makes it more readable.

Line 4: func main() {} is a function. Any code inside its curly brackets {} will be executed.

Line 5: fmt.Println() is a function made available from the fmt package. It is used to output/print text. In our example it will output "Hello World!".

Go Statements

fmt.Println("Hello World!") is a statement.

In Go, statements are separated by ending a line (hitting the Enter key) or by a semicolon ";".

Hitting the Enter key adds ";" to the end of the line implicitly (does not show up in the source code).

The left curly bracket { cannot come at the start of a line.

Run the following code and see what happens:

Go Compact Code

You can write more compact code, like shown below (this is not recommended because it makes the code more difficult to read):

package main
import ("fmt")

func main() {
  ("Hello World!")
}