JavaScript Expressions Complete Reference Last Updated : 23 Jul, 2025 Comments Improve Suggest changes 2 Likes Like Report JavaScript's expression is a valid set of literals, variables, operators, and expressions that evaluate a single value that is an expression. This single value can be a number, a string, or a logical value depending on the expression. Example: JavaScript // Illustration of function* expression // use of function* keyword function* func() { yield 1; yield 2; yield 3; yield " - Geeks"; } let obj = ''; // Function calling for (const i of func()) { obj = obj + i; } // Output console.log(obj); Output123 - GeeksThe Complete List of JavaScript Expressions is listed below: JavaScript Primary Expressions Expressions Description Example this keywordThat defines the current line of code’s execution context. Try Async/Await FunctionChecks that we are not breaking the execution thread. Try Object initializer They have properties and methods attached to them and properties are in the form of key-value pairs. Try Grouping operatorThe Grouping operator consists of a pair of parentheses around an expression. Try async function The async function is declared using the async keyword. Try Regular ExpressionsThe search pattern can be used for text search and text to replace operations.function* ExpressionDefine a generator function inside an expression. Try Function ExpressionDefine a function inside an expression. Try class ExpressionThe class name is used internally, but not outside of the class. Try Create Quiz Comment K kartik Follow 2 Improve K kartik Follow 2 Improve Article Tags : JavaScript Web Technologies Explore JavaScript BasicsIntroduction to JavaScript4 min readVariables and Datatypes in JavaScript6 min readJavaScript Operators5 min readControl Statements in JavaScript4 min readArray & StringJavaScript Arrays7 min readJavaScript Array Methods7 min readJavaScript Strings5 min readJavaScript String Methods9 min readFunction & ObjectFunctions in JavaScript5 min readJavaScript Function Expression3 min readFunction Overloading in JavaScript4 min readObjects in JavaScript4 min readJavaScript Object Constructors4 min readOOPObject Oriented Programming in JavaScript3 min readClasses and Objects in JavaScript4 min readWhat Are Access Modifiers In JavaScript ?5 min readJavaScript Constructor Method7 min readAsynchronous JavaScriptAsynchronous JavaScript2 min readJavaScript Callbacks4 min readJavaScript Promise4 min readEvent Loop in JavaScript4 min readAsync and Await in JavaScript2 min readException HandlingJavascript Error and Exceptional Handling6 min readJavaScript Errors Throw and Try to Catch2 min readHow to create custom errors in JavaScript ?2 min readJavaScript TypeError - Invalid Array.prototype.sort argument1 min readDOMHTML DOM (Document Object Model)8 min readHow to select DOM Elements in JavaScript ?3 min readJavaScript Custom Events4 min readJavaScript addEventListener() with Examples9 min readAdvanced TopicsClosure in JavaScript4 min readJavaScript Hoisting6 min readScope of Variables in JavaScript3 min readJavaScript Higher Order Functions7 min readDebugging in JavaScript4 min read Like