Constants in classes in Ruby - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a constant named GREETING inside the class.

Ruby

class Welcome
  [1] = "Hello!"
end

Drag options to blanks, or click blank then click option'

AGreeting

BgREETING

Cgreeting

DGREETING

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase letters for constant names.

Using variable names instead of constants.

The constant name must start with a capital letter. Here, GREETING is the correct constant name.

2fill in blank

medium

Complete the code to access the constant PI inside the class MathConstants.

Ruby

class MathConstants
  PI = 3.14

  def self.get_pi
    [1]
  end
end

Drag options to blanks, or click blank then click option'

API

BMathConstants.pi

Cself.PI

Dpi

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase letters to access constants.

Trying to call constants like methods.

Constants are accessed by their exact name. Inside the class method, PI refers to the constant.

3fill in blank

hard

Fix the error in accessing the constant MAX_SPEED from outside the class Vehicle.

Ruby

class Vehicle
  MAX_SPEED = 120
end

speed = [1]

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AVehicle->MAX_SPEED

BVehicle.MAX_SPEED

CVehicle::MAX_SPEED

DVehicle.MAXspeed

Attempts:

3 left

💡 Hint

Common Mistakes

Using dot notation instead of double colon.

Using incorrect operator like '->'.

In Ruby, constants from outside a class are accessed using the double colon :: operator.

4fill in blank

hard

Fill both blanks to define and access a constant SPEED_LIMIT inside the class Car.

Ruby

class Car
  [1] = 80

  def speed_limit
    [2]
  end
end

Drag options to blanks, or click blank then click option'

ASPEED_LIMIT

Bspeed_limit

Dself.SPEED_LIMIT

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase names for constants.

Trying to access constants with dot notation inside instance methods.

The constant SPEED_LIMIT is defined and accessed by its name inside the class.

5fill in blank

hard

Fill all three blanks to create a constant NAME, access it inside a method, and access it from outside the class Person.

Ruby

class Person
  [1] = "Alice"

  def name
    [2]
  end
end

puts [3]

Drag options to blanks, or click blank then click option'

ANAME

CPerson::NAME

Dname

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase names for constants.

Trying to access constants like instance variables.

Using dot notation outside the class.

The constant NAME is defined and accessed inside the class by its name, and from outside using Person::NAME.