In the realm of programming, the terms ‘expressions’ and ‘operators’ are frequently used. But what do they mean? Let’s delve into these concepts to gain a better understanding.
What is an Expression?
An expression, at its core, is a valid unit of code that resolves to a value. It’s like a mathematical equation that computes a result. For instance, in the equation 5 + 3, 5 + 3 is an expression that resolves to 8.
Expressions in programming come in two types:
Expressions with side effects: These expressions do something more than just compute a value. They might change the state of the program in some way. For example, the expression
x = 7assigns the value7to the variablex. This expression has a side effect (assigning a value tox) and also evaluates to7.Purely evaluative expressions: These expressions simply compute a value and do nothing else. For example, the expression
3 + 4adds3and4together to produce7. However, if this expression isn’t part of a larger construct (like a variable declaration, such asconst z = 3 + 4), its result will be immediately discarded. This is usually a programmer mistake because the evaluation doesn’t produce any effects.
What is an Operator?
Operators are the building blocks of expressions. They’re like the mathematical symbols that perform operations on values. In the expression 3 + 4, the + is an operator that performs addition.
In the world of programming, there are many different operators, such as:
=: The assignment operator, which assigns a value to a variable.+: The addition operator, which adds two numbers together.-: The subtraction operator, which subtracts one number from another.*: The multiplication operator, which multiplies two numbers together./: The division operator, which divides one number by another.
And many more.
In conclusion, understanding expressions and operators is fundamental to programming. They form the basis of how we write and understand code. Whether you’re assigning values, performing calculations, or controlling the flow of your program, you’ll be using expressions and operators. So, the next time you see x = 7 or 3 + 4 in your code, you’ll know exactly what’s going on!
A Comprehensive Guide to JavaScript Operators
Operators are fundamental to any programming language, and JavaScript is no exception. They allow us to perform operations on our data, manipulate it, and create logic in our code. Let’s explore the different types of operators in JavaScript.
Assignment Operators
An assignment operator assigns a value to its left operand based on the value of its right operand. The simple assignment operator is =, which assigns the value of its right operand to its left operand. For example, x = f() is an assignment expression that assigns the value of f() to x.
Comparison Operators
Comparison operators compare values and return true or false. The operators include: >, <, >=, <=, ==, ===, != and !==.
Arithmetic Operators
Arithmetic operators perform addition, subtraction, multiplication, division, exponentiation, and remainder operations. They include:
+(Addition)-(Subtraction)*(Multiplication)**(Exponentiation)/(Division)%(Modulus i.e., Remainder)++(Increment)--(Decrement)
Bitwise Operators
Bitwise operators treat arguments as 32-bits (zeros & ones) and work on the level of their binary representation. For example, the decimal number 9 has a binary representation of 1001. Bitwise operators perform their operations on such binary representations but return standard JavaScript numerical values. They include:
&(AND)|(OR)^(XOR)~(NOT)<<(Left SHIFT)>>(Right SHIFT)>>>(Zero-Fill Right SHIFT)
Logical Operators
There are four logical operators in JavaScript: || (OR), && (AND), ! (NOT), ?? (Nullish Coalescing).
BigInt Operators
Most operators that can be used with the Number data type will also work with BigInt values (e.g., arithmetic, comparison, etc.). However, the unsigned right shift >>> operator is an exception and is not supported. Similarly, some operators may have slight differences in behavior (for example, division with BigInt will round towards zero).
String Operators
In addition to the comparison operators, which can be used on string values, the concatenation operator + concatenates two string values together, returning another string that is the union of the two operand strings. The shorthand assignment operator += can also be used to concatenate strings.
Conditional Operators
The conditional operator, also known as the ternary operator, is the only JavaScript operator that takes three operands. The operator can have one of two values based on a condition. The syntax is: condition ? val_for_true : val_for_false.
Comma Operators
The comma operator (,) evaluates each of its operands (from left to right) and returns the value of the last operand. This lets you create a compound expression in which multiple expressions are evaluated, with the compound expression’s final value being the value of the rightmost of its member expressions. This is commonly used to provide multiple parameters to a for loop.
Unary Operators
JavaScript Unary Operators are the special operators that consider a single operand and perform all the types of operations on that single operand. These operators include unary plus, unary minus, prefix increments, postfix increments, prefix decrements, and postfix decrements.
Relational Operators
Relational operators, also known as comparison operators, are used to find the relationship between two values or compare the relationship between them; on the comparison, they yield the result true or false.
Understanding these operators is crucial for writing efficient and effective JavaScript code. They allow us to manipulate data, control the flow of our programs, and implement complex logic. Happy coding!
Comments
Post a Comment