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What are lambda expressions or arrow functions

Arrow functions (also known as "lambda expressions") provide a concise syntax for writing function expressions in JavaScript. Introduced in ES6, arrow functions are often shorter and more readable, especially for simple operations or callbacks.

Key Features:

  • Arrow functions do not have their own this, arguments, super, or new.target bindings. They inherit these from their surrounding (lexical) context.
  • They are best suited for non-method functions, such as callbacks or simple computations.
  • Arrow functions cannot be used as constructors and do not have a prototype property.
  • They also cannot be used with new, yield, or as generator functions.

Syntax Examples:

const arrowFunc1 = (a, b) => a + b;    // Multiple parameters, returns a + b
const arrowFunc2 = a => a * 10;        // Single parameter (parentheses optional), returns a * 10
const arrowFunc3 = () => {};           // No parameters, returns undefined
const arrowFunc4 = (a, b) => {
// Multiple statements require curly braces and explicit return
const sum = a + b;
return sum * 2;
};
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