Heredoc syntax for multiline strings in Ruby - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is heredoc syntax in Ruby?

Heredoc syntax allows you to create multiline strings easily by using << followed by an identifier, then the string content, and ending with the same identifier on its own line.

beginner

How do you start a heredoc string in Ruby?

You start a heredoc string with << followed by an identifier, for example <

beginner

How do you end a heredoc string in Ruby?

You end a heredoc string by placing the same identifier used to start it on its own line, with no extra spaces or characters.

intermediate

What is the difference between <

<

intermediate

How can you create a heredoc string that does not process escape sequences or interpolation?

Use single quotes around the identifier like <<'EOF'. This creates a literal string where escape sequences and interpolation are not processed.

Which of the following correctly starts a heredoc string in Ruby?

A <<TEXT

B <TEXT

C <<<TEXT

D <-TEXT

Heredoc strings start with << followed by an identifier like TEXT.

How must the ending identifier of a heredoc appear when using <

A At the start of the line with no spaces

B Inside quotes

C On the same line as the string content

D Indented with spaces

The ending identifier must be at the start of the line with no spaces when using <

What does <<-'EOF' do differently than <

A Starts a single-line string

B Disables string interpolation

C Allows the ending identifier to be indented

D Ends the string immediately

<<-EOF allows the ending identifier to be indented, making code formatting easier.

How do you create a heredoc string that treats content literally (no interpolation or escape sequences)?

A <<EOF

B <<'EOF'

C <<-EOF

D <<"EOF"

Using single quotes around the identifier like <<'EOF' creates a literal string.

What will this Ruby code output? str = <

A Error

B Hello\nWorld

C Hello World

D Hello World

Heredoc with <

Explain how to write a multiline string using heredoc syntax in Ruby.

Think about how you mark the start and end of the string.

Describe the difference between <

Focus on indentation and string processing differences.