File.readlines for line-by-line in Ruby - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to read all lines from a file named 'data.txt' into an array.

Ruby

lines = File.[1]('data.txt')

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

Agets

Bread

Copen

Dreadlines

Attempts:

3 left

💡 Hint

Common Mistakes

Using File.read returns the whole file as a single string, not an array of lines.

Using File.open returns a file object, not the lines directly.

The File.readlines method reads all lines from the file and returns them as an array.

2fill in blank

medium

Complete the code to print each line from the file 'notes.txt' using File.readlines.

Ruby

File.[1]('notes.txt').each do |line|
  puts line
end

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

Areadlines

Bforeach

Copen

Dread

Attempts:

3 left

💡 Hint

Common Mistakes

Using File.read returns a string, which does not have an each method for lines.

Using File.foreach reads lines one by one but is not called on File.readlines.

File.readlines reads all lines into an array, which you can then iterate over with each.

3fill in blank

hard

Fix the error in the code to correctly read lines from 'log.txt' and print them.

Ruby

lines = File.[1]('log.txt')
lines.each do |line|
  puts line
end

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

Aread

Breadlines

Copen

Dgets

Attempts:

3 left

💡 Hint

Common Mistakes

Using File.read returns a string, which cannot be iterated line by line with each.

Using File.open returns a file object, not an array of lines.

File.readlines returns an array of lines, so you can iterate over it with each.

4fill in blank

hard

Fill both blanks to create a hash with line numbers as keys and lines as values from 'input.txt'.

Ruby

lines = File.[1]('input.txt')
line_hash = lines.each_with_index.to_h { |[2], i| [i + 1, [2]] }

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

Areadlines

Bline

Dread

Attempts:

3 left

💡 Hint

Common Mistakes

Using File.read instead of File.readlines returns a string, which does not work with each_with_index as expected.

Using a wrong variable name in the block causes errors.

File.readlines reads all lines into an array. Using each_with_index with a block lets you create a hash with line numbers as keys.

5fill in blank

hard

Fill all three blanks to create a hash with uppercase line keys and their lengths as values from 'file.txt'.

Ruby

lines = File.[1]('file.txt')
result = lines.to_h { |[2]| [[2].upcase, [3] ] }

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

Aread

Breadlines

Cline.length

Dline

Attempts:

3 left

💡 Hint

Common Mistakes

Using File.read returns a string, which cannot be iterated like an array.

Mixing variable names or forgetting to call upcase causes errors.

File.readlines reads lines into an array. Using to_h with a block creates a hash with uppercase lines as keys and their lengths as values.