More Rails Features

Flashcard 1 of 8

Heredocs are a handy way of defining multi-line strings:

instructions = <<-INSTRUCTIONS
Here is a long set of instructions.

You've got to do a lot of things:

1. This thing.
2. That thing.
3. Even more
INSTRUCTIONS

One issue you might encounter is defining a heredoc in some code that is indented:

class Messages
  def self.welcome
    <<-WELCOME
This is the welcome message.

However, because it's a heredoc, we need to unindent it all the way out :(. 

Otherwise Ruby thinks the indentation we include is part of the string.
WELCOME
  end
end

How can we have our heredocs and maintain our usual indentation scheme?

Answer:

Reveal Answer

strip_heredoc to the rescue!

class Messages
  def self.welcome
    <<-WELCOME.strip_heredoc
      This is the welcome message.

      Since we're using strip_heredoc, we can indent it as usual.

      Much nicer, no?
    WELCOME
  end
end

strip_heredoc will trim leading whitespace to match the first line, allowing you to keep your code neat and tidy within your method block.

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