JavaScript Functions Lab

Introduction

This lab provides an opportunity to practice defining and coding some real-world functions.

Note: Feel free to work in pairs to complete this lab. Also, Google/StackOverflow is a good friend to have around...

Exercise

Setup & Instructions

Create a new HTML/CSS/JS repl in repl.it for these exercises.

Title your repl JS Function Lab.

This lab is not a deliverable.

Requirements

Define and code the functions below.

Define the functions using the approach as specified (either as a function expression or declaration).

Be sure to number each function with a comment above it.

After each function, call it at least once and console.log the results.

For example, here's the first function, our gift to you:

// 1.
function maxOfTwoNumbers(x, y) {
  if (x >= y) {
    return x;
  } else {
    return y;
  }
  
  // or more "elegantly" using the fantastic ternary expression!
  // return  x >= y ? x : y;
}

console.log(maxOfTwoNumbers(3, 9));

// 2.
...

Here are the functions:

  1. (completed above) Define a function, as a function declaration, maxOfTwoNumbers that takes two numbers as arguments and returns the largest of them. If they are the same, return that number. Use the if-else construct or a ternary expression - the Math.max method is not allowed.
  2. Define a function, as a function expression, maxOfThree that takes three numbers as arguments and returns the largest of them. Again, the Math.max method is not allowed.
  3. Define a function, as a function declaration, isCharAVowel that takes a character as an argument and returns true if it is a vowel, false otherwise.
  4. Define a function, as a function expression, sumArray that takes an array of numbers and returns the sum of those numbers. For example, sumArray([2, 4, 5]); would return 11.
  5. Define a function, as a function declaration, multiplyArray that takes an array of numbers and returns the product those numbers. For example, multiplyArray([2, 4, 5]); would return 40.
  6. Define a function, as a function expression, numArgs that returns the number of arguments passed to the function when called.
  7. Define a function, as a function declaration, reverseString that takes a string, reverses the characters, and returns it. For example, reverseString('rockstar'); would return the string "ratskcor".
  8. Define a function, as a function expression, longestStringInArray that takes an array of strings as an argument and returns the length of the longest string.
  9. Define a function, as a function declaration, stringsLongerThan that takes an array of strings and a number as arguments; and returns an array of the strings that are longer than the number passed in. For example, stringsLongerThan(['say', 'hello', 'in', 'the', 'morning'], 3); would return ["hello", "morning"].

Solution Code

Try not to peek!

Additional Resources