A function definition inside an another function is known as Nested Function. It is not supported by C++, Java, etc. In other languages, we can call a function inside a function, but it’s not a nested function. In Scala, we can define functions inside a function and functions defined inside other functions are called nested or local functions.
Syntax:
def FunctionName1( parameter1, parameter2, ..) = {
def FunctionName2() = {
// code
}
}
Single Nested Function
Here is an example of single nested function that takes two numbers as parameters and returns the Maximum and Minimum of them.
Example
Scala
// Scala program of Single Nested Function
object MaxAndMin
{
// Main method
def main(args: Array[String])
{
println("Min and Max from 5, 7")
maxAndMin(5, 7);
}
// Function
def maxAndMin(a: Int, b: Int) = {
// Nested Function
def maxValue() = {
if(a > b)
{
println("Max is: " + a)
}
else
{
println("Max is: " + b)
}
}
// Nested Function
def minValue() = {
if (a < b)
{
println("Min is: " + a)
}
else
{
println("Min is: " + b)
}
}
maxValue();
minValue();
}
}
Output
Min and Max from 5, 7
Max is: 7
Min is: 5
In above code maxAndMin is a function and maxValue is another inner function returns maximum value between a and b similarly minValue is another inner function which is also nested function this function returns minimum value between a and b.
Multiple Nested Function
Here is an implementation of multiple nested function.
Example
Scala
// Scala program of Multiple Nested Function
object MaxAndMin
{
// Main method
def main(args: Array[String])
{
fun();
}
// Function
def fun() = {
geeks();
// First Nested Function
def geeks() = {
println("geeks");
gfg();
// Second Nested Function
def gfg() = {
println("gfg");
geeksforgeeks();
// Third Nested Function
def geeksforgeeks() = {
println("geeksforgeeks");
}
}
}
}
}
Output
geeks
gfg
geeksforgeeks
In above code fun is a function and geeks, gfg, geeksforgeeks are nested functions or local function .
Similar Reads
Interview Preparation
Practice @Geeksforgeeks
Data Structures
Algorithms
Programming Languages
Web Technologies
Computer Science Subjects
Data Science & ML
Tutorial Library
GATE CS