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Golang iota Constant with Examples

Golang | iota Constant: Here, we are going to learn about the iota constant with examples.
Submitted by IncludeHelp, on October 12, 2021

iota Constant

In the Go programming language, iota is an untyped int type of value that is a predeclared identifier (represents the untyped integer ordinal number of the current const specification in a (usually parenthesized) const declaration). It is zero-indexed.

Syntax:

iota

Parameter(s):

• None

Return Value:

None

Example 1:

// Golang program to demonstrate the
// example of iota constant

package main

import (
	"fmt"
)

func main() {
	const x = iota

	// Printing the value and type
	// of x
	fmt.Printf("x: %T, %v\n", x, x)

	// Declaring multiple constants
	const (
		a = iota
		b = iota
		c = iota
	)

	// Printing the values and types
	// of a, b, and c
	fmt.Printf("a: %T, %v\n", a, a)
	fmt.Printf("b: %T, %v\n", b, b)
	fmt.Printf("c: %T, %v\n", c, c)
}

Output:

x: int, 0
a: int, 0
b: int, 1
c: int, 2

Example 2:

// Golang program to demonstrate the
// example of iota constant

package main

import (
	"fmt"
)

func main() {
	// Declaring multiple constants
	const (
		a = iota
		b
		c
	)

	const (
		x = iota + 10
		y
		z
	)

	// Printing the values and types
	// of a, b, and c
	fmt.Printf("a: %T, %v\n", a, a)
	fmt.Printf("b: %T, %v\n", b, b)
	fmt.Printf("c: %T, %v\n", c, c)

	// Printing the values and types
	// of x, y, and z
	fmt.Printf("x: %T, %v\n", x, x)
	fmt.Printf("y: %T, %v\n", y, y)
	fmt.Printf("z: %T, %v\n", z, z)
}

Output:

a: int, 0
b: int, 1
c: int, 2
x: int, 10
y: int, 11
z: int, 12

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