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Arrow Functions (ES6)

// Arrow function with two arguments const sum = (firstParam, secondParam) => { return firstParam + secondParam; }; console.log(sum(2,5)); // Prints: 7 // Arrow function with no arguments const printHello = () => { console.log('hello'); }; printHello(); // Prints: hello // Arrow functions with a single argument const checkWeight = weight => { console.log(`Baggage weight : ${weight} kilograms.`); }; checkWeight(25); // Prints: Baggage weight : 25 kilograms. // Concise arrow functions const multiply = (a, b) => a * b; console.log(multiply(2, 30)); // Prints: 60

Arrow function expressions were introduced in ES6. These expressions are clean and concise. The syntax for an arrow function expression does not require the function keyword and uses a fat arrow => to separate the parameter(s) from the body.

There are several variations of arrow functions:

  • Arrow functions with a single parameter do not require () around the parameter list.
  • Arrow functions with a single expression can use the concise function body which returns the result of the expression without the return keyword.
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  2. 2
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  3. 3
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  4. 4
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  5. 5
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  6. 6
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  7. 7
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  8. 8
    Another way to define a function is to use a function expression. To define a function inside an expression, we can use the function keyword. In a function expression, the function name is usuall…
  9. 9
    ES6 introduced arrow function syntax, a shorter way to write functions by using the special “fat arrow” () => notation. [Arrow functions](…
  10. 10
    JavaScript also provides several ways to refactor arrow function syntax. The most condensed form of the func…
  11. 11
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