assignment statement meaning in computer language

• Assignment Statement

An Assignment statement is a statement that is used to set a value to the variable name in a program .

Assignment statement allows a variable to hold different types of values during its program lifespan. Another way of understanding an assignment statement is, it stores a value in the memory location which is denoted by a variable name.

The symbol used in an assignment statement is called as an operator . The symbol is ‘=’ .

Note: The Assignment Operator should never be used for Equality purpose which is double equal sign ‘==’.

The Basic Syntax of Assignment Statement in a programming language is :

variable = expression ;

variable = variable name

expression = it could be either a direct value or a math expression/formula or a function call

Few programming languages such as Java, C, C++ require data type to be specified for the variable, so that it is easy to allocate memory space and store those values during program execution.

data_type variable_name = value ;

In the above-given examples, Variable ‘a’ is assigned a value in the same statement as per its defined data type. A data type is only declared for Variable ‘b’. In the 3 rd line of code, Variable ‘a’ is reassigned the value 25. The 4 th line of code assigns the value for Variable ‘b’.

Assignment Statement Forms

This is one of the most common forms of Assignment Statements. Here the Variable name is defined, initialized, and assigned a value in the same statement. This form is generally used when we want to use the Variable quite a few times and we do not want to change its value very frequently.

Tuple Assignment

Generally, we use this form when we want to define and assign values for more than 1 variable at the same time. This saves time and is an easy method. Note that here every individual variable has a different value assigned to it.

(Code In Python)

Sequence Assignment

(Code in Python)

Multiple-target Assignment or Chain Assignment

In this format, a single value is assigned to two or more variables.

Augmented Assignment

In this format, we use the combination of mathematical expressions and values for the Variable. Other augmented Assignment forms are: &=, -=, **=, etc.

Browse more Topics Under Data Types, Variables and Constants

• Concept of Data types
• Built-in Data Types
• Constants in Programing Language 
• Access Modifier
• Variables of Built-in-Datatypes
• Declaration/Initialization of Variables
• Type Modifier

Few Rules for Assignment Statement

Few Rules to be followed while writing the Assignment Statements are:

• Variable names must begin with a letter, underscore, non-number character. Each language has its own conventions.
• The Data type defined and the variable value must match.
• A variable name once defined can only be used once in the program. You cannot define it again to store other types of value.
• If you assign a new value to an existing variable, it will overwrite the previous value and assign the new value.

FAQs on Assignment Statement

Q1. Which of the following shows the syntax of an  assignment statement ?

• variablename = expression ;
• expression = variable ;
• datatype = variablename ;
• expression = datatype variable ;

Answer – Option A.

Q2. What is an expression ?

• Same as statement
• List of statements that make up a program
• Combination of literals, operators, variables, math formulas used to calculate a value
• Numbers expressed in digits

Answer – Option C.

Q3. What are the two steps that take place when an  assignment statement  is executed?

• Evaluate the expression, store the value in the variable
• Reserve memory, fill it with value
• Evaluate variable, store the result
• Store the value in the variable, evaluate the expression.

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Kenneth Leroy Busbee

An assignment statement sets and/or re-sets the value stored in the storage location(s) denoted by a variable name; in other words, it copies a value into the variable. [1]

The assignment operator allows us to change the value of a modifiable data object (for beginning programmers this typically means a variable). It is associated with the concept of moving a value into the storage location (again usually a variable). Within most programming languages the symbol used for assignment is the equal symbol. But bite your tongue, when you see the = symbol you need to start thinking: assignment. The assignment operator has two operands. The one to the left of the operator is usually an identifier name for a variable. The one to the right of the operator is a value.

Simple Assignment

The value 21 is moved to the memory location for the variable named: age. Another way to say it: age is assigned the value 21.

Assignment with an Expression

The item to the right of the assignment operator is an expression. The expression will be evaluated and the answer is 14. The value 14 would be assigned to the variable named: total_cousins.

Assignment with Identifier Names in the Expression

The expression to the right of the assignment operator contains some identifier names. The program would fetch the values stored in those variables; add them together and get a value of 44; then assign the 44 to the total_students variable.

• cnx.org: Programming Fundamentals – A Modular Structured Approach using C++
• Wikipedia: Assignment (computer science) ↵

Programming Fundamentals Copyright © 2018 by Kenneth Leroy Busbee is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License , except where otherwise noted.

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Variable Assignment

To "assign" a variable means to symbolically associate a specific piece of information with a name. Any operations that are applied to this "name" (or variable) must hold true for any possible values. The assignment operator is the equals sign which SHOULD NEVER be used for equality, which is the double equals sign.

The '=' symbol is the assignment operator. Warning, while the assignment operator looks like the traditional mathematical equals sign, this is NOT the case. The equals operator is '=='

Design Pattern

To evaluate an assignment statement:

• Evaluate the "right side" of the expression (to the right of the equal sign).
• Once everything is figured out, place the computed value into the variables bucket.

We've already seen many examples of assignment. Assignment means: "storing a value (of a particular type) under a variable name" . Think of each assignment as copying the value of the righthand side of the expression into a "bucket" associated with the left hand side name!

Read this as, the variable called "name" is "assigned" the value computed by the expression to the right of the assignment operator ('=');

Now that you have seen some variables being assigned, tell me what the following code means?

The answer to above questions: the assignment means that lkjasdlfjlskdfjlksjdflkj is a variable (a really badly named one), but a variable none-the-less. jlkajdsf and lkjsdflkjsdf must also be variables. The sum of the two numbers held in jlkajdsf and lkjsdflkjsdf is stored in the variable lkjasdlfjlskdfjlksjdflkj.

Examples of builtin Data and Variables (and Constants)

For more info, use the "help" command: (e.g., help realmin);

Examples of using Data and Variable

Pattern to memorize, assignment pattern.

The assignment pattern creates a new variable, if this is the first time we have seen the "name", or, updates the variable to a new value!

Read the following code in English as: First, compute the value of the thing to the right of the assignment operator (the =). then store the computed value under the given name, destroying anything that was there before.

Or more concisely: assign the variable "name" the value computed by "right_hand_expression"

• Table of Contents
• Course Home
• Assignments
• Peer Instruction (Instructor)
• Peer Instruction (Student)
• Change Course
• Instructor's Page
• Progress Page
• Edit Profile
• Change Password
• Scratch ActiveCode
• Scratch Activecode
• Instructors Guide
• About Runestone
• Report A Problem
• 1.1 Getting Started
• 1.1.1 Preface
• 1.1.2 About the AP CSA Exam
• 1.1.3 Transitioning from AP CSP to AP CSA
• 1.1.4 Java Development Environments
• 1.1.5 Growth Mindset and Pair Programming
• 1.1.6 Pretest for the AP CSA Exam
• 1.1.7 Survey
• 1.2 Why Programming? Why Java?
• 1.3 Variables and Data Types
• 1.4 Expressions and Assignment Statements
• 1.5 Compound Assignment Operators
• 1.6 Casting and Ranges of Values
• 1.7 Unit 1 Summary
• 1.8 Mixed Up Code Practice
• 1.9 Toggle Mixed Up or Write Code Practice
• 1.10 Coding Practice
• 1.11 Multiple Choice Exercises
• 1.12 Method Signatures (preview 2026 curriculum)
• 1.13 Calling Class Methods (preview 2026 curriculum)
• 1.3. Variables and Data Types" data-toggle="tooltip">
• 1.5. Compound Assignment Operators' data-toggle="tooltip" >

Time estimate: 90 min.

1.4. Expressions and Assignment Statements ¶

In this lesson, you will learn about assignment statements and expressions that contain math operators and variables.

1.4.1. Assignment Statements ¶

Assignment statements initialize or change the value stored in a variable using the assignment operator = . An assignment statement always has a single variable on the left hand side. The value of the expression (which can contain math operators and other variables) on the right of the = sign is stored in the variable on the left.

Figure 1: Assignment Statement (variable = expression;) ¶

Instead of saying equals for the = in an assignment statement, say “gets” or “is assigned” to remember that the variable gets or is assigned the value on the right. In the figure above score is assigned the value of the expression 10 times points (which is another variable) plus 5.

The following video by Dr. Colleen Lewis shows how variables can change values in memory using assignment statements.

As we saw in the video, we can set one variable’s value to a copy of the value of another variable like y = x; . This won’t change the value of the variable that you are copying from.

Let’s step through the following code in the Java visualizer to see the values in memory. Click on the Next button at the bottom of the code to see how the values of the variables change. You can run the visualizer on any Active Code in this e-book by just clicking on the Code Lens button at the top of each Active Code.

Activity: CodeLens 1.4.1.2 (asgnviz1)

1-4-3: What are the values of x, y, and z after the following code executes? You can step through this code by clicking on this Java visualizer link.

• x = 0, y = 1, z = 2
• These are the initial values in the variable, but the values are changed.
• x = 1, y = 2, z = 3
• x changes to y's initial value, y's value is doubled, and z is set to 3
• x = 2, y = 2, z = 3
• Remember that the equal sign doesn't mean that the two sides are equal. It sets the value for the variable on the left to the value from evaluating the right side.
• x = 0, y = 0, z = 3

The following has the correct code to ‘swap’ the values in x and y (so that x ends up with y’s initial value and y ends up with x’s initial value), but the code is mixed up and contains one extra block which is not needed in a correct solution. Drag the needed blocks from the left into the correct order on the right. Check your solution by clicking on the Check button. You will be told if any of the blocks are in the wrong order or if you need to remove one or more blocks. After three incorrect attempts you will be able to use the Help Me button to make the problem easier.

1.4.2. Adding 1 to a Variable ¶

If you use a variable to keep score, you would probably increment it (add one to the current value) whenever score should go up. You can do this by setting the variable to the current value of the variable plus one ( score = score + 1 ) as shown below. The formula would look strange in math class, but it makes sense in coding because it is assigning a new value to the variable on the left that comes from evaluating the arithmetic expression on the right. So, the score variable is set to the previous value of score plus 1.

Try the code below to see how score is incremented by 1. Try substituting 2 instead of 1 to see what happens.

1.4.3. Input with Variables ¶

Variables are a powerful abstraction in programming because the same algorithm can be used with different input values saved in variables. The code below using the Scanner class will say hello to anyone who types in their name and will have different results for different name values. First, type in your name below the code and then click on run. Try again with a friend’s name. The code works for any name: behold, the power of variables!

The code below will say hello to anyone who types in their name. Type in your name below the code and then click on run. Try again with a friend’s name.

Although you will not be tested in the AP CSA exam on using the Java input or the Scanner or Console classes, learning how to do input in Java is very useful and fun. For more information on using the Scanner class, go to https://www.w3schools.com/java/java_user_input.asp , and for the newer Console class, https://howtodoinjava.com/java-examples/console-input-output/ . We are limited with the one way communication with the Java server in this Runestone ebook, but in most IDEs like replit, the input/output would be more interactive. Here are some examples in replit for Java Scanner Input Repl using the Scanner class and Java Console Input Repl using the Console class that you can try out.

1.4.4. Operators ¶

Java uses the standard mathematical operators for addition ( + ), subtraction ( - ), and division ( / ). The multiplication operator is written as * , as it is in most programming languages, since the character sets used until relatively recently didn’t have a character for a real multiplication sign, × , and keyboards still don’t have a key for it. Likewise no ÷ .

You may be used to using ^ for exponentiation, either from a graphing calculator or tools like Desmos. Confusingly ^ is an operator in Java, but it has a completely different meaning than exponentiation and isn’t even exactly an arithmetic operator. You will learn how to use the Math.pow method to do exponents in Unit 2.

Arithmetic expressions can be of type int or double . An arithmetic expression consisting only of int values will evaluate to an int value. An arithmetic expression that uses at least one double value will evaluate to a double value. (You may have noticed that + was also used to combine String and other values into new String s. More on this when we talk about String s more fully in Unit 2.)

Java uses the operator == to test if the value on the left is equal to the value on the right and != to test if two items are not equal. Don’t get one equal sign = confused with two equal signs == . They mean very different things in Java. One equal sign is used to assign a value to a variable. Two equal signs are used to test a variable to see if it is a certain value and that returns true or false as you’ll see below. Also note that using == and != with double values can produce surprising results. Because double values are only an approximation of the real numbers even things that should be mathematically equivalent might not be represented by the exactly same double value and thus will not be == . To see this for yourself, write a line of code below to print the value of the expression 0.3 == 0.1 + 0.2 ; it will be false !

Run the code below to see all the operators in action. Do all of those operators do what you expected? What about 2 / 3? Isn’t it surprising that it prints 0? See the note below about truncating division with integers. Change the code to make it print the decimal part of the division too. You can do this by making at least one of the numbers a double like 2.0.

When Java sees you doing integer division (or any operation with integers) it assumes you want an integer result so it throws away anything after the decimal point in the answer. This is called truncating division . If you need a double answer, you should make at least one of the values in the expression a double like 2.0.

With division, another thing to watch out for is dividing by 0. An attempt to divide an integer by zero will result in an ArithmeticException error message. Try it in one of the active code windows above.

Operators can be used to create compound expressions with more than one operator. You can either use a literal value which is a fixed value like 2, or variables in them. When compound expressions are evaluated, operator precedence rules are used, just like when we do math (remember PEMDAS?), so that * , / , and % are done before + and - . However, anything in parentheses is done first. It doesn’t hurt to put in extra parentheses if you are unsure as to what will be done first or just to make it more clear.

In the example below, try to guess what it will print out and then run it to see if you are right. Remember to consider operator precedence . How do the parentheses change the precedence?

1.4.5. The Remainder Operator ¶

The operator % in Java is the remainder operator. Like the other arithmetic operators is takes two operands. Mathematically it returns the remainder after dividing the first number by the second, using truncating integer division. For instance, 5 % 2 evaluates to 1 since 2 goes into 5 two times with a remainder of 1.

While you may not have heard of remainder as an operator, think back to elementary school math. Remember when you first learned long division, before they taught you about decimals, how when you did a long division that didn’t divide evenly, you gave the answer as the number of even divisions and the remainder. That remainder is what is returned by this operator. In the figures below, the remainders are the same values that would be returned by 2 % 3 and 5 % 2 .

Figure 1: Long division showing the integer result and the remainder ¶

Sometimes people—including Professor Lewis in the next video—will call % the modulo , or mod , operator. That is not actually correct though the difference between remainder and modulo, which uses Euclidean division instead of truncating integer division, only matters when negative operands are involved and the signs of the operands differ. With positive operands, remainder and mod give the same results. Java does have a method Math.floorMod in the Math class if you need to use modulo instead of remainder, but % is all you need in the AP exam.

Here’s the video .

In the example below, try to guess what it will print out and then run it to see if you are right.

The result of x % y when x is smaller than y is always x. The value y can’t go into x at all (goes in 0 times), since x is smaller than y, so the result is just x. So if you see 2 % 3 the result is 2.

1-4-11: What is the result of 158 % 10?

• This would be the result of 158 divided by 10. % gives you the remainder.
• % gives you the remainder after the division.
• When you divide 158 by 10 you get a remainder of 8.

1-4-12: What is the result of 3 % 8?

• 8 goes into 3 no times so the remainder is 3. The remainder of a smaller number divided by a larger number is always the smaller number!
• This would be the remainder if the question was 8 % 3 but here we are asking for the reminder after we divide 3 by 8.
• What is the remainder after you divide 3 by 8?

1.4.6. Programming Challenge : Dog Years ¶

In this programming challenge, you will calculate your age, and your pet’s age from your birthdates, and your pet’s age in dog years. In the code below, type in the current year, the year you were born, the year your dog or cat was born (if you don’t have one, make one up!) in the variables below. Then write formulas in assignment statements to calculate how old you are, how old your dog or cat is, and how old they are in dog years which is 7 times a human year. Finally, print it all out. If you are pair programming, switch drivers (who has control of the keyboard in pair programming) after every line of code.

Calculate your age and your pet’s age from the birthdates, and then your pet’s age in dog years.

Your teacher may suggest that you use a Java IDE like replit.com for this challenge so that you can use input to get these values using the Scanner class . Here is a repl template that you can use to get started if you want to try the challenge with input.

1.4.7. Summary ¶

Arithmetic expressions include expressions of type int and double .

The arithmetic operators consist of + , - , * , / , and % also known as addition, subtraction, multiplication, division, and remainder.

An arithmetic operation that uses two int values will evaluate to an int value. With integer division, any decimal part in the result will be thrown away.

An arithmetic operation that uses at least one double value will evaluate to a double value.

Operators can be used to construct compound expressions.

During evaluation, operands are associated with operators according to operator precedence to determine how they are grouped. ( * , / , % have precedence over + and - , unless parentheses are used to group those.)

An attempt to divide an integer by zero will result in an ArithmeticException .

The assignment operator ( = ) allows a program to initialize or change the value stored in a variable. The value of the expression on the right is stored in the variable on the left.

During execution, expressions are evaluated to produce a single value.

The value of an expression has a type based on the types of the values and operators used in the expression.

1.4.8. AP Practice ¶

The following is a 2019 AP CSA sample question.

1-4-14: Consider the following code segment.

What is printed when the code segment is executed?

• 0.666666666666667
• Don't forget that division and multiplication will be done first due to operator precedence.
• Yes, this is equivalent to (5 + ((a/b)*c) - 1).
• Don't forget that division and multiplication will be done first due to operator precedence, and that an int/int gives an int truncated result where everything to the right of the decimal point is dropped.

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Difference between declaration statement and assignment statement in C? [duplicate]

I am new to programming and trying to learn C. I am reading a book where I read about these statements but could not understand their meaning.

2 Answers 2

Declaration:

Assignment:

Declaration and assignment in one statement:

Declaration says, "I'm going to use a variable named " a " to store an integer value." Assignment says, "Put the value 3 into the variable a ."

(As @delnan points out, my last example is technically initialization , since you're specifying what value the variable starts with, rather than changing the value. Initialization has special syntax that also supports specifying the contents of a struct or array.)

• 6 The third isn't an assignment. It's initalization. –  user395760 Commented Apr 22, 2014 at 18:33
• 6 It matters in C insofar you can do things in initialization that you can't do in assignment. For example int a[2] = {}; works but int a[2]; a = {}; doesn't. –  user395760 Commented Apr 22, 2014 at 18:41

Declaring a variable sets it up to be used at a later point in the code. You can create variables to hold numbers, characters, strings (an array of characters), etc.

You can declare a variable without giving it a value. But, until a variable has a value, it's not very useful.

You declare a variable like so: char myChar; NOTE: This variable is not initialized.

Once a variable is declared, you can assign a value to it, like: myChar = 'a'; NOTE: Assigning a value to myChar initializes the variable.

To make things easier, if you know what a variable should be when you declare it, you can simply declare it and assign it a value in one statement: char myChar = 'a'; NOTE: This declares and initializes the variable.

So, once your myChar variable has been given a value, you can then use it in your code elsewhere. Example:

This prints the value of myChar and myOtherChar to stdout (the console), and looks like:

If you had declared char myChar; without assigning it a value, and then attempted to print myChar to stdout, you would receive an error telling you that myChar has not been initialized.

• You mostly describe the difference between declaring a variable and not initializing it vs. declaring a variable and initializing it. –  user395760 Commented Apr 22, 2014 at 18:42

Not the answer you're looking for? Browse other questions tagged c difference or ask your own question .

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Assignment Operators in Programming

Assignment operators in programming are symbols used to assign values to variables. They offer shorthand notations for performing arithmetic operations and updating variable values in a single step. These operators are fundamental in most programming languages and help streamline code while improving readability.

Table of Content

What are Assignment Operators?

• Types of Assignment Operators
• Assignment Operators in C
• Assignment Operators in C++
• Assignment Operators in Java
• Assignment Operators in Python
• Assignment Operators in C#
• Assignment Operators in JavaScript
• Application of Assignment Operators

Assignment operators are used in programming to  assign values  to variables. We use an assignment operator to store and update data within a program. They enable programmers to store data in variables and manipulate that data. The most common assignment operator is the equals sign ( = ), which assigns the value on the right side of the operator to the variable on the left side.

Types of Assignment Operators:

• Simple Assignment Operator ( = )
• Addition Assignment Operator ( += )
• Subtraction Assignment Operator ( -= )
• Multiplication Assignment Operator ( *= )
• Division Assignment Operator ( /= )
• Modulus Assignment Operator ( %= )

Below is a table summarizing common assignment operators along with their symbols, description, and examples:

Assignment Operators in C:

Here are the implementation of Assignment Operator in C language:

Assignment Operators in C++:

Here are the implementation of Assignment Operator in C++ language:

Assignment Operators in Java:

Here are the implementation of Assignment Operator in java language:

Assignment Operators in Python:

Here are the implementation of Assignment Operator in python language:

Assignment Operators in C#:

Here are the implementation of Assignment Operator in C# language:

Assignment Operators in Javascript:

Here are the implementation of Assignment Operator in javascript language:

Application of Assignment Operators:

• Variable Initialization : Setting initial values to variables during declaration.
• Mathematical Operations : Combining arithmetic operations with assignment to update variable values.
• Loop Control : Updating loop variables to control loop iterations.
• Conditional Statements : Assigning different values based on conditions in conditional statements.
• Function Return Values : Storing the return values of functions in variables.
• Data Manipulation : Assigning values received from user input or retrieved from databases to variables.

Conclusion:

In conclusion, assignment operators in programming are essential tools for assigning values to variables and performing operations in a concise and efficient manner. They allow programmers to manipulate data and control the flow of their programs effectively. Understanding and using assignment operators correctly is fundamental to writing clear, efficient, and maintainable code in various programming languages.

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Statement vs Expression – What's the Difference in Programming?

By Ogundiran Ayobami

Learning the syntax of a programming language is key if you want to use that language effectively. This is true for both new and experienced developers.

And one of the most important things to pay attention to while learning a programming language is whether the code you're dealing with is a statement or an expression.

It can sometimes be confusing to differentiate between statements and expressions in programming. So this article is meant to simplify the differences so that you can improve your programming skills and become a better developer.

What is an Expression in Programming?

An expression is any word or group of words or symbols that is a value. In programming, an expression is a value, or anything that executes and ends up being a value.

It is necessary to understand that a value is unique. For example, const , let , 2 , 4 , s , a , true , false , and world are values because each of them is unique in meaning or character.

Let's look at some code as an example:

Judging from the code above, const , price , = , and 500 are expressions because each of them has a definite and unique meaning or value. But if we take all of them together const price = 500 - then we have a statement.

Let's look at another example:

Looking at the code above, you can see an anonymous function is assigned to a variable. Oh, wait! You might know that any function is a statement. Can it also be an expression?

Yes! A "function" and a "class" are both statements and expressions because they can perform actions (do or not do tasks) and still execute to a value.

This brings us to statements – so what are they?

What is a Statement in Programming?

A statement is a group of expressions and/or statements that you design to carry out a task or an action.

Statements are two-sided – that is, they either do tasks or don't do them. Any statement that can return a value is automatically qualified to be used as an expression. That is why a function or class is a statement and also an expression in JavaScript.

If you look at the example of the function under the section on expressions, you can see it is assigned and execute to a value passed to a variable. That is why it is an expression in that case.

Examples of Statements in Programming

Inline statements.

The whole of the code above is a statement because it carries out the task of assigning $2000 to amount . It is safe to say a line of code is a statement because most compilers or interpreters don't execute any standalone expression.

Block statements

Look at the below if statement:

The if statement is a statement because it helps us check whether I love you or not. As I have said before, it is two-sided: this code finds out whether "I love you" or not, and that is why it is a statement. Also, it doesn't return any value but it can create side effects.

Here's a loop statement:

In short, any loop is a statement because if it can only do the tasks it is meant to do or not – does loop and doesn't loop. But a loop can't execute to a value in the end. They can only have side effects in JavaScript. Once they can execute to a value in a programming language, then they can also be used as an expression.

For example, you can use forloop and if statement as expressions in Python.

There is also an "IF" expression in Python. That means that something that is a statement in one language can be an expression (or both statement and expression) in another.

Look at the below function statement:

We declare the function add(firstNumber, secondNumber) and it returns a value. The function is called with two arguments as in add(2, 3) by declaration and so it is a statement. If you pay close attention, you will realize that calling the function as a statement is useless since it has no side effect.

Hey, stop! How can we turn it into an expression? Oh yeah, we can do it like this:

Though the function is now an expression the way it is called above, the whole of the code is still a statement.

Check out this class statement:

You can see that we declare the class "Person" and instantiate and assign it to "User" immediately. So, it is used as an expression.

Now, let's use it as a statement:

A class is similar to a function in the sense that it can be declared, assigned, or used as an operand just like a class. So, a class is a statement and/or an expression.

The Main Differences Between an Expression and a Statement in Programming

Expressions can be assigned or used as operands, while statements can only be declared.

Statements create side effects to be useful, while expressions are values or execute to values.

Expressions are unique in meaning, while statements are two-sided in execution. For example, 1 has a certain value while go( ) may be executed or not.

Statements are the whole structure, while expressions are the building blocks. For example, a line or a block of code is a statement.

Why You Should Know the Difference

First of all, understanding the difference between statements and expressions should make learning new programming languages less surprising. If you're used to JavaScript, you may be surprised by Python's ability to assign an if statement as a variable which is not possible in JavaScript.

Second, it makes it easy to use programming paradigms across different programming languages.

For example, a JavaScript "if statement" cannot be used as an expression because it can't execute to a value – it can only create side effects. Yet, you can use the ternary operator if you want to avoid the side effects of using an if statement in JavaScript.

For this reason, you can understand why some programmers avoid if statements by using the ternary operator in JavaScript. It is because they want to avoid side effects .

It also makes your realize why you have to be always careful about the scope of your variables whenever you use a statement. This is true because statements mostly have side effects to be useful, and it is reasonable to understand the scope of your variables and operations. For example,

Hey wait! What would be logged in the console if you ran the code above?

Tell yourself the answer first and then paste the code in the console to confirm. If you you're wrong, you need to learn more about scope and side effects. But if you're right, try to make those functions a bit better to avoid the confusion they may generate.

Knowing the difference also helps you to easily identify non-composable and composable syntaxes (functions, classes, modules, and so on) of a programming language. This makes porting your experience from one programming language to another more interesting and direct.

Wrapping Up

Now that you understand the difference between expressions and statements in programming, and you know why understanding the differences is important, you can identify pieces of code as expressions or statements while coding.

Next time, we'll go even further and help make learning a second programming language easier.

Go and get things done now! See you soon.

I am planning to share a lot about programming tips and tutorials in 2023. If you're struggling to build projects or you want to stay connected with my write-ups and videos, please join my list at YouTooCanCode or subscribe to my YouTube channel at You Too Can Code on YouTube .

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