Define_method with closures in Ruby - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a method named 'greet' that returns 'Hello'.

Ruby

class Person
  define_method(:greet) do
    [1]
  end
end

p = Person.new
puts p.greet

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

A"Hello"

BHello

Creturn Hello

Dputs "Hello"

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting quotes around Hello, causing a NameError.

Using puts inside the method instead of returning a string.

The method should return the string "Hello". Using quotes makes it a string literal.

2fill in blank

medium

Complete the code to define a method 'add' that takes one argument and adds it to 10.

Ruby

class Calculator
  define_method(:add) do |num|
    [1]
  end
end

calc = Calculator.new
puts calc.add(5)

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

A10 + num

Bnum + 10

Cnum - 10

D10 - num

Attempts:

3 left

💡 Hint

Common Mistakes

Subtracting instead of adding.

Swapping the order causing confusion.

Adding 10 to the argument num returns the sum. Both 'num + 10' and '10 + num' work.

3fill in blank

hard

Fix the error in the code to correctly define a method 'multiplier' that multiplies input by a fixed factor.

Ruby

class Multiplier
  def initialize(factor)
    @factor = factor
  end

  define_method(:multiply) do |num|
    num [1] @factor
  end
end

m = Multiplier.new(3)
puts m.multiply(4)

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

A/

B+

C-

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Using addition or subtraction instead of multiplication.

Using division which changes the result.

To multiply the input number by the factor, use the '*' operator.

4fill in blank

hard

Fill both blanks to define a method 'power' that raises input to a fixed exponent stored in @exp.

Ruby

class Power
  def initialize(exp)
    @exp = exp
  end

  define_method(:power) do |base|
    base [1] @exp
  end
end

p = Power.new(2)
puts p.power(5)

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

A**

B*

C+

D-

Attempts:

3 left

💡 Hint

Common Mistakes

Using multiplication instead of exponentiation.

Using addition or subtraction operators.

The '**' operator in Ruby raises a number to the power of another number.

5fill in blank

hard

Fill all three blanks to define a method 'describe' that returns a string with the object's name and age.

Ruby

class Person
  def initialize(name, age)
    @name = name
    @age = age
  end

  define_method(:describe) do
    "[1] is [2] years old."
  end
end

person = Person.new("Alice", 30)
puts person.describe

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

A@name

B@age

C"#{@name}"

D"#{@age}"

Attempts:

3 left

💡 Hint

Common Mistakes

Using variables without interpolation, resulting in literal text.

Using instance variables without quotes inside the string.

To insert instance variables into a string, use string interpolation with "#{variable}" syntax.