Functional Programming Tutorial
Functional Programming Resources
Selected Reading
- File I/O Operations
- Lazy Evaluation
- Lambda Calculus
- Records
- Tuple
- Lists
- Strings
- Polymorphism
- Data Types
- Higher Order Functions
- Recursion
- Function Overriding
- Function Overloading
- Call By Reference
- Call By Value
- Function Types
- Functions Overview
- Introduction
- Home
Functional Programming Resources
Selected Reading
- Who is Who
- Computer Glossary
- HR Interview Questions
- Effective Resume Writing
- Questions and Answers
- UPSC IAS Exams Notes
Call By Reference
Functional Programming - Call By Reference
In Call by Reference, the original value is changed because we pass reference address of arguments. The actual and formal arguments share the same address space, so any change of value inside the function is reflected inside as well as outside the function.
Call by Reference in C++
The following program shows how Call by Value works in C++ −
#include <iostream>
using namespace std;
void swap(int *a, int *b) {
int temp;
temp = *a;
*a = *b;
*b = temp;
cout<<"
"<<"value of a inside the function: "<<*a;
cout<<"
"<<"value of b inside the function: "<<*b;
}
int main() {
int a = 50, b = 75;
cout<<"
"<<"value of a before sending to function: "<<a;
cout<<"
"<<"value of b before sending to function: "<<b;
swap(&a, &b); // passing value to function
cout<<"
"<<"value of a after sending to function: "<<a;
cout<<"
"<<"value of b after sending to function: "<<b;
return 0;
}
It will produce the following output −
value of a before sending to function: 50 value of b before sending to function: 75 value of a inside the function: 75 value of b inside the function: 50 value of a after sending to function: 75 value of b after sending to function: 50
Call by Reference in Python
The following program shows how Call by Value works in Python −
def swap(a,b):
t = a;
a = b;
b = t;
print "value of a inside the function: :",a
print "value of b inside the function: ",b
return(a,b)
# Now we can call swap function
a = 50
b =75
print "value of a before sending to function: ",a
print "value of b before sending to function: ",b
x = swap(a,b)
print "value of a after sending to function: ", x[0]
print "value of b after sending to function: ",x[1]
It will produce the following output −
value of a before sending to function: 50 value of b before sending to function: 75 value of a inside the function: 75 value of b inside the function: 50 value of a after sending to function: 75 value of b after sending to function: 50Advertisements