Triple single quote vs triple double quote in Ruby

Question

Why might you use ''' instead of """, as in Learn Ruby the Hard Way, Chapter 10 Study Drills?

Answer 1

There are no triple quotes in Ruby.

Two String literals which are juxtaposed are parsed as a single String literal. So,

'Hello' 'World'
#=> "HelloWorld"

is the same as

'HelloWorld'
#=> "HelloWorld"

And

'' 'Hello' ''
#=> "Hello"

is the same as

'''Hello'''
#=> "Hello"

is the same as

'Hello'
#=> "Hello"

Since adding an empty string literal does not change the result, you can add as many empty strings as you want:

""""""""""""'''''Hello'''''''''
#=> "Hello"

There are no special rules for triple single quotes vs. triple double quotes, because there are no triple quotes. The rules are simply the same as for quotes.

Answer 2

I assume the author confused Ruby and Python, because a triple-quote will not work in Ruby the way author thought it would. It'll just work like three separate strings ('' '' '').

For multi-line strings one could use:

%q{
 your text
 goes here
}
 => "\n     your text\n     goes here\n    "

or %Q{} if you need string interpolation inside.