Go: Design Patterns for Real-World Projects

Visibility

Visibility is the attribute of a function or a variable to be visible to different parts of the program. So a variable can be used only in the function that is declared, in the entire package or in the entire program.

How can I set the visibility of a variable or function? Well, it can be confusing at the beginning but it cannot be simpler:

• Uppercase definitions are public (visible in the entire program).
• Lowercase are private (not seen at the package level) and function definitions (variables within functions) are visible just in the scope of the function.

Here you can see an example of a public function:

package hello 
 
func Hello_world(){ 
    println("Hello World!") 
} 

Here, Hello_world is a global function (a function that is visible across ...