Best way to escape and unescape strings in Ruby?

Question

Does Ruby have any built-in method for escaping and unescaping strings? In the past, I've used regular expressions; however, it occurs to me that Ruby probably does such conversions internally all the time. Perhaps this functionality is exposed somewhere.

So far I've come up with these functions. They work, but they seem a bit hacky:

def escape(s)   s.inspect[1..-2] end  def unescape(s)   eval %Q{"#{s}"} end 

Is there a better way?

Answer 1

Ruby 2.5 added String#undump as a complement to String#dump:

$ irb irb(main):001:0> dumped_newline = "\n".dump => "\"\\n\"" irb(main):002:0> undumped_newline = dumped_newline.undump => "\n" 

With it:

def escape(s)   s.dump[1..-2] end  def unescape(s)   "\"#{s}\"".undump end  $irb irb(main):001:0> escape("\n \" \\") => "\\n \\\" \\\\" irb(main):002:0> unescape("\\n \\\" \\\\") => "\n \" \\" 

Answer 2

There are a bunch of escaping methods, some of them:

# Regexp escapings >> Regexp.escape('\*?{}.')    => \\\*\?\{\}\.  >> URI.escape("test=100%") => "test=100%25" >> CGI.escape("test=100%") => "test%3D100%25" 

So, its really depends on the issue you need to solve. But I would avoid using inspect for escaping.

Update - there is a dump, inspect uses that, and it looks like it is what you need:

>> "\n\t".dump => "\"\\n\\t\""