10 Differences Between Ruby and JavaScript

Aymes S.
Aymes S.
Oct 9, 2020 · 4 min read

1. Printing Out the Functions

In Ruby, we are familiar with “puts, print, p, and pp.” In Javascript, we use “console.log()” to have a return.

def who_lives_in_a_pineapple_under_the_sea
puts "Spongebob Squarepants!"
function whoLivesInAPineappleUnderTheSea(){
console.log("Spongebob Squarepants!");

2. The Each Method

This method is a way to iterate through an array of elements in order to return, change, or manipulate them.

spongebob_chars = ["Spongebob", "Patrick", "Sandy", "Plankton"]
spongebob_chars.each {|single_char| puts single_char}
#=> "Spongebob", "Patrick", "Sandy", "Plankton"
let spongebobChars = ["Spongebob", "Patrick", "Sandy", "Plankton"]
spongebobChars.forEach(function(singleChar) {
//=> "Spongebob", "Patrick", "Sandy", "Plankton"

3. Hashes and Objects


spongebob_hash = {name: "Spongebob Squarepants", pet: "Gary the Snail", occupation: "Fry Cook"}spongebob_hash[:pet] #=> "Gary the Snail"
let spongebob = {name: "Spongebob Squarepants", pet: "Gary the Snail", occupation: "Fry Cook"};spongebob.pet //=> "Gary the Snail"

4. Determining a Value of Something


squidward = "Squidward"squidward.class #=> String
let squidward = "Squidward";typeof(squidward) //=> String

5. Making Comments


# f is for friends who do stuff together
// u is for you and me
/* n is for anywhere
and anytime at all
down here in the deep
blue sea! */

6. Incrementing and Decrementing

To increment or decrement by 1 in JavaScript, we can write ++or - -. In Ruby, it is +=. We can also write += in JavaScript if we want to increment or decrement by a number larger than 1. (+= 2 to add by two or -=5 to subtract by 5)

while x < 5
puts x
x += 1
let x = 0; 
while (x < 5){

7. == vs ===

Ruby only has = and == while JavaScript has all three, =, ==, and ===.

25 == "25"
//=> true
25 == 25
//=> true
25 === "25"
//=> false
25 === 25
//=> true

8. Declaring Variables

Both Ruby and JavaScript have different ways of defining variables.

x = "krabby patty" 
# can only be used in its scope
GLOBALVARIABLE = "krabby patty"
# can be used throughout the whole program
# note that the variable name must be capitalized
var plankton = "Plankton";function getkrabbyPatty {
var secretFormula = "The Secret Formula";
//=> secretFormula is undefined
for {let x = 1; x < 5; x++
//=> 1, 2, 3, 4
const krabbypatty = "Krabby Patty";
const krabbypatty = "Pretty Patty";
//=> error 'krabbypatty' has already been declared

9. If/Else and Switch Statements

Ruby and JavaScript both have if/else statements, but JavaScript also has something called Switch statements. Remember that we useIf if a specified condition is true, else if the same condition is false, and elsif (Ruby) or else if (JavaScript) if the first condition is false.

puts "Who's Dirty Dan?"
dirtydan = gets.chomp # getting a user's input
if dirtydan == "Spongebob"
puts "Spongebob is Dirty Dan"
elsif dirtydan == "Patrick"
puts "Patrick is Dirty Dan"
puts "Try again"
if (dirtydan === "Spongebob"){
console.log("Spongebob is Dirty Dan";
} else if (dirtydan === "Patrick"){
console.log("Patrick is Dirty Dan");
} else {
console.log("Sandy's going to find out either way!");
var dirtydan = "Patrick";
switch (dirtydan){
case "Spongebob":
console.log("Spongebob is Dirty Dan");
case "Patrick":
console.log("Patrick is Dirty Dan");
console.log("Sandy's going to find out either way!");

10. String Interpolation


mayonnaise = "Mayonnaise"
puts "Is #{mayonnaise} an instrument?"
let mayonnaise = "Mayonnaise"; 
console.log(`Is ${mayonnaise} an instrument?`);

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Aymes S.

Written by

Aymes S.

Software Engineer in the making.

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