What are different between declaration & definition?

Asked by Last Modified  

4 Answers

Learn C Language

Follow 0
Answer

Please enter your answer

Declaration means defining the variable or function. Definition means group of instruction or group of statement to be performed when function is call. It defined the task of function.
Comments
Dislike Bookmark

A declaration introduces an identifier and describes its type, be it a type, object, or function. A declaration is what the compiler needs to accept references to that identifier. These are declarations: extern int bar; extern int g(int, int); double f(int, double); // extern can be omitted for...
read more
A declaration introduces an identifier and describes its type, be it a type, object, or function. A declaration is what the compiler needs to accept references to that identifier. These are declarations: extern int bar; extern int g(int, int); double f(int, double); // extern can be omitted for function declarations class foo; // no extern allowed for type declarations A definition actually instantiates/implements this identifier. It's what the linker needs in order to link references to those entities. These are definitions corresponding to the above declarations: int bar; int g(int lhs, int rhs) {return lhs*rhs;} double f(int i, double d) {return i+d;} class foo {}; A definition can be used in the place of a declaration. An identifier can be declared as often as you want. Thus, the following is legal in C and C++: double f(int, double); double f(int, double); extern double f(int, double); // the same as the two above extern double f(int, double); read less
Comments
Dislike Bookmark

GATE Qualified

Declaration tells the compiler the presence of a variable named so and so in the program. Definition assigns the memory address to the variable. The best example of declaration and definition is: struct var { int a; char b; }; This is only declaration because no object is created of var type. Whereas,...
read more
Declaration tells the compiler the presence of a variable named so and so in the program. Definition assigns the memory address to the variable. The best example of declaration and definition is: struct var { int a; char b; }; This is only declaration because no object is created of var type. Whereas, If we do int x; in main() function, then it is declaration and definition as well because compiler gets to know about x and memory location is also assigned to x. read less
Comments
Dislike Bookmark

Thanks for the question Rajinder...... Declaring a variable means to inform the compiler that the variable is declared of this data type. Variable definition means to ask the compiler for memory. Thanks, Team DishaaPro www.dishaapro.com
Comments
Dislike Bookmark

View 2 more Answers

Related Questions

How do I learn C programming easily?
Just follow kanitkar book of c programming for beginners
Harsh
0 0
5
Why are operating systems written in C? Why aren't other languages used?
Operating systems are often written in C due to a combination of historical reasons, performance considerations, and system-level functionality provided by the language. C is a low-level programming language...
Deepa
0 0
7
What does %d mean in the C programming language?
signed decimal integer %d is not the only format specifier in C to represent integers. To be precise, %d is used to represent a signed decimal integer.
Vikas
0 0
6
How do I execute the Java program?
javac nameofprogram.java java nameofprogram note***:Name of program should be same as that of your class name having main method *** above steps are used to execute programs on command line
Sharmistha
0 0
6
What is "&" called in C language?
The Address Operator in C also called a pointer. This address operator is denoted by “&”. This & symbol is called an ampersand.
Soumya
0 0
5

Now ask question in any of the 1000+ Categories, and get Answers from Tutors and Trainers on UrbanPro.com

Ask a Question

Related Lessons

Program to swap the value of two variables without using third variable(simplest way)...
int main() { int a=10,b=20; printf("values of a before swap ="%d,a); printf("values of b before swap ="%d,b); a=a+b; b=a-b; a=a-b; printf("******************"); printf("values of a after swap...

Rohan

2 0
1
Creating First Program Using C Language
Step 1: Install and setup Turbo C compiler on your computer. Step 2: Open Turbo C from your Desktop or Programs menu. Select “File” from menu bar and select option “New”. Step...

Dipti S.

0 0
0
C Program-Infinite Loop[For] Demo
//Header Files #include<stdio.h>#include<conio.h> //Main function void main(){ //Function for clearing screen clrscr(); //Infinite for loop for(;;) { printf("Hello!"); } //Function for...

Salim Ahmed Ansari

0 0
0
C Program-Upper Case Demo
/*WAP to print the character entered by user in upper case*/ //Header files #include<stdio.h>#include<conio.h> //Main function void main(){ char ch; //Function for clearing screen clrscr(); ...

Salim Ahmed Ansari

0 0
0
What Would Be Life Cycle Of A Fresher After Campus In An IT Company?
1. Basic Technical Training: Since freshers are not subject matter experts so gone through 3 - 6 months basic technical training within Organization. 2. Technical Assessment: HR sends freshers to various...

Amit K.

0 0
0

Recommended Articles

Brilliant Academy, a reputed B. Tech Tuition...

Brilliant Academy is one of the reputed institutes for B.Tech tuition classes. This institute is specialised in delivering quality tuition classes for B.E, Engineering - all streams and Engineering diploma courses. Incorporated in 2012, Brillant Academy is a brainchild of Mr Jagadeesh. The main motto of the academy is to...

Read full article >

Lasya Infotech: An educational Training...

Lasya Infotech is a Hyderabad based IT training institute founded in 2016 by O Venkat. Believing in his innovation, passion and persistence and with a diverse blend of experience, he started his brainchild to deliver exemplary professional courses to aspiring candidates by honing their skills. Ever since the institute envisions...

Read full article >

Why Should you Become an IT Consultant

Information technology consultancy or Information technology consulting is a specialized field in which one can set their focus on providing advisory services to business firms on finding ways to use innovations in information technology to further their business and meet the objectives of the business. Not only does...

Read full article >

Make a Career in Mobile Application Programming

Almost all of us, inside the pocket, bag or on the table have a mobile phone, out of which 90% of us have a smartphone. The technology is advancing rapidly. When it comes to mobile phones, people today want much more than just making phone calls and playing games on the go. People now want instant access to all their business...

Read full article >

Find C Language Classes near you
C Language Classes in Bangalore
C Language Classes in Hyderabad
C Language Classes in Delhi
C Language Classes in Pune
C Language Classes in Chennai
C Language Classes in Mumbai
C Language Classes in Kolkata
C Language Classes in Noida
C Language Classes in Ghaziabad
C Language Classes in Gurgaon

Looking for C Language Classes?

Learn from the Best Tutors on UrbanPro

Are you a Tutor or Training Institute?

Join UrbanPro Today to find students near you