Implicit return (last expression) in Ruby - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to return the sum of two numbers without using the return keyword.

Ruby

def add(a, b)
  a [1] b
end

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

A+

B-

C/

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Using subtraction or multiplication instead of addition.

Trying to use the return keyword explicitly.

The last expression a + b is implicitly returned by the method.

2fill in blank

medium

Complete the code to implicitly return the length of the string.

Ruby

def length_of_string(str)
  str.[1]
end

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

Asize

Bcount

Cchars

Dlength

Attempts:

3 left

💡 Hint

Common Mistakes

Using chars which returns an array, not a number.

Using count without arguments returns 0.

The method length returns the number of characters in the string, and since it's the last expression, it is implicitly returned.

3fill in blank

hard

Fix the error in the method to implicitly return the square of the number.

Ruby

def square(num)
  num [1] 2
end

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

A**

B*

C^

Dpow

Attempts:

3 left

💡 Hint

Common Mistakes

Using * which multiplies but does not square.

Using ^ which is a bitwise XOR, not exponentiation.

In Ruby, ** is the exponentiation operator. Using it correctly returns the square of the number implicitly.

4fill in blank

hard

Fill both blanks to create a method that returns the last character of a string implicitly.

Ruby

def last_char(str)
  str[1][2]
end

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

A[0]

B.last

C[-1]

D.first

Attempts:

3 left

💡 Hint

Common Mistakes

Using [0] or .first which return the first character.

Mixing index and method incorrectly.

Using str[-1] or str.last returns the last character. Both are valid ways to implicitly return the last character.

5fill in blank

hard

Fill all three blanks to create a method that returns a hash with keys as uppercase words and values as their lengths, implicitly.

Ruby

def word_lengths(words)
  words.each_with_object([1]) do |word, result|
    result[[2]] = word.[3]
  end
end

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

A{}

Bword.upcase

Clength

D[]

Attempts:

3 left

💡 Hint

Common Mistakes

Using square brackets [] instead of an empty hash {}.

Using word instead of word.upcase as keys.

Using size or other methods instead of length.

The method uses each_with_object({}) to build a hash. The key is the uppercase word word.upcase, and the value is the length of the word word.length. The last expression is implicitly returned.