Class instance variables as alternative in Ruby - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a class instance variable in Ruby.

Ruby

class MyClass
  [1] = 10
end

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

A@@value

B@@count

C@value

D@count

Attempts:

3 left

💡 Hint

Common Mistakes

Using '@@' instead of '@' for class instance variables.

Defining variables inside methods instead of the class body.

Class instance variables start with a single @ inside the class body but outside any method.

2fill in blank

medium

Complete the code to access a class instance variable inside a class method.

Ruby

class MyClass
  @count = 5

  def self.get_count
    [1]
  end
end

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

A@count

B@@count

Cself.@count

Dcount

Attempts:

3 left

💡 Hint

Common Mistakes

Using '@@count' which refers to class variables, not class instance variables.

Trying to use 'self.@count' which is invalid syntax.

Inside a class method, you can access class instance variables directly with @variable.

3fill in blank

hard

Fix the error in the code to correctly initialize and access a class instance variable.

Ruby

class MyClass
  [1] = 0

  def self.get_value
    @value
  end
end

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

A@value

B@@value

Cself.@value

Dvalue

Attempts:

3 left

💡 Hint

Common Mistakes

Initializing class instance variables inside instance methods.

Using '@@' for class instance variables.

To initialize a class instance variable, assign it with '@value' inside the class body or class methods, not inside instance methods like initialize.

4fill in blank

hard

Fill both blanks to create a class instance variable and a class method that returns it.

Ruby

class MyClass
  [1] = 100

  def self.get_value
    [2]
  end
end

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

A@value

B@@value

D@@count

Attempts:

3 left

💡 Hint

Common Mistakes

Using '@@' instead of '@' for class instance variables.

Trying to access class instance variables with wrong syntax.

Class instance variables use a single '@' and can be accessed inside class methods with '@variable'.

5fill in blank

hard

Fill all three blanks to define a class instance variable, a class method to set it, and a class method to get it.

Ruby

class MyClass
  [1] = nil

  def self.set_value(val)
    [2] = val
  end

  def self.get_value
    [3]
  end
end

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

A@value

D@@value

Attempts:

3 left

💡 Hint

Common Mistakes

Using '@@value' instead of '@value'.

Trying to set class instance variables inside instance methods.

Class instance variables use '@value'. You can set and get them inside class methods using '@value'.