Ruby and Python

Recently I just started learning Python and got confused by how similar the way it’s written is to the one Ruby is written. So this time I’ll be taking a note of comparison between Ruby and Python.

Conceptual difference

Ruby is designed for the concept “Enjoy programming.”, which let you write codes in various ways and have more freedom on coding Ruby than any other programming languages. Instead, the more freely you code, the less readable your code gets on coding Ruby.

On the other hand, Python is designed for the concept “The Zen of Python”, which leads every Python code to look similar because of the strict rules or syntax.

Declaration and execution of function

Python requires you to put () right after the function name when either declaring or executing it. On the contrary, Ruby doesn’t.

Ruby

def greeting
  put "Hello, world!"
end

greeting

Python

def greeting():
    print("Hello, world!")

greeting()

If statement

The ways both Ruby and Python recognize if statement are quite similar as you see below. (elsif => elif, next => continue, etc..)

Ruby

print "Enter a number! "
num = gets.to_i

if num > 8
  puts num.to_s + " is bigger than 8"
elsif num < 8
  puts num.to_s + " is smaller than 8"
else
  puts num.to_s + " is equal to 8"
end

Python

input_value = input("Enter a number! ")
num = int(input_value)

if int(num) > 8:
    print(str(num) + " is bigger than 8")
elif num < 8:
    print(str(num) + " is smaller than 8")
else:
    print(str(num) + " is equal to 8")

Loops

Ruby and Python has quite much syntax in common when it comes to Loops like for loop and while loop below.

ruby

# for loop
for i in 1..8 do # do is omittable
  puts i
end

# while loop
num = 1
while num <= 8 do # do is omittable
  p num
  num += 1
end

（Ruby has more sorts of loops such as times, upto, loop, etc..）

Python

# for loop
for i in range(1,8):
    print(i)

# while loop
num = 1
while num <= 8:
    print(num)
    num += 1

Operator

Ruby

age = 22
if age >= 20 && age < 30
  puts "私は20代です"
end

pref = "Hiroshima"
if pref == "Osaka" || pref == "Hiroshima"
  puts "出身地は大阪か広島です"
end

Python

age = 22
if age >= 20 and age < 30:
    print("私は20代です")

pref = "Hiroshima"
if pref == "Osaka" or pref == "Hiroshima":
    print("出身地は大阪か広島です")

Class and Instance

How to declare and generate instance in Python is something I’m not familiar with. In Python, you need to put in self as an argument of methods.

Ruby

class Greeting
  def initialize(name)
    @name = name
  end

  def say_hello
    puts "Hello, #{@name}!"
  end
end

greeting = Greeting.new("Tomoya")
greeting.say_hello

Python

class Greeting:
    def __init__(self, name):
        self.name = name

    def say_hello(self):
        print("Hello, " + self + "!")

    name = "Tomoya"
    say_hello(name)

P. S.

The we code Python has some mashup-ish syntax of Ruby and JavaScript, which I found really interesting. ( like putting () after functions, elif can look like JavaScript’s else if turns into Ruby’s elsif and ends up with being elif ) Also, I somehow feel similarity on how Python use constructor to initialize a instance because I’ve been writing a similar one on React recently.

Python has tuple and list which work in a similar ways of const and let in JavaScript. There must be more interesting points that I haven’t make on this post.

I’ll keep look for those similarities on the journey of mastering Python and Ruby.

Tomoya