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The Variables in Go Programming

The variable in Go points to some memory location that stores some type of value.

A variable is only a name given to a storage space that the applications can control. Each variable in Go includes a particular type, which determines the size and layout in the memory.

A few rules of Go variables are:

  • The name of a variable could be composed of letters, digits, and the underscore character.
  • It has to start with a letter or an underscore.
  • Upper and lowercase letters are different because Go is case-sensitive.
  • It is possible to declare a number of variables at the same time.
  • Go will evaluate the kind of all initialized variables.
Declaring go variable

This is how Go variables are declared:

var <variable_name> <type>

So, you have to use the “var” keyword.

The type parameter(from the above syntax) signifies the sort of value which may be kept in the memory place.

The basic type of variable includes:

  • byte
  • int
  • float32
  • complex64
  • boolean
  • user-defined object etc.
Further Reading:  The Function in Go Language
An example of declaring the variable in Go

You may declare variables in different ways in Go. Follow are a few examples:

var  x, y

var  x, y, z int

var  chr byte

var  amount float32

 

All the above are valid declarations in Go.

Declaring the variables with values

This is how you may assign a value to the variable at the time of declaration:

var <var_name> = <var_value>

For example:

var x = 20

Omitting the var keyword as declaring variables

You may also use the shorthand for declaring and initializing the variable in Go. For that, use the := as shown below:

<var_name > := <var_value>

An example Go program of variable

In the example below, we have declared a variable. This is followed by assigning a value and then displaying the value:

package main


import "fmt"



func main() {

var x int

x = 100

fmt.Println(x)

}

The output:

100

Another example with different variations

See this example where we declared variables in various ways and displayed values:


 

Further Reading:  What is a Range in Go Language?

The output:

Some Value

5 10

Another example with var

This example shows declaring without var keyword as well.

package main


import "fmt"


func main() {

var b = true

fmt.Println(b)


ani := "lion"

fmt.Println(f)

}

 

The output:

true

lion

Note: Variables declared with No initial value will have of 0 for numeric types, false for the Boolean and empty string for strings.