Variables

In Go, variable declaration is straightforward but follows specific rules for type assignment and initialization

1. Basic Variable Declaration

You can declare a variable with the var keyword, followed by the variable name, its type, and an optional initial value.

var <name> <type> = <value>

// Example
var age int = 25
var name string = "Alice"

If you don't provide an initial value, the variable will be initialized with the zero value for its type. For example, an int will default to 0, a string will default to "" (empty string), and a bool will default to false.

var age int // age is automatically set to 0
var isActive bool // isActive is automatically set to false

2. Short Declaration (Type Inference)

Go allows you to declare variables without explicitly specifying their type using the := operator. The type is inferred from the initial value.

<name> := <value>

// Example
age := 30
name := "Bob"

This shorthand form can only be used inside functions, not at the package level.

3. Multiple Variable Declaration

You can declare multiple variables in one line, separated by commas. This can be done with the var keyword or the shorthand :=.

var x, y, z int = 1, 2, 3
a, b := 10, 20

4. Constant Declaration

Go also supports constant declarations using the const keyword. Constants are immutable and must be initialized with a value at the time of declaration.

const <name> <type> = <value>

const pi float64 = 3.14159