How to strip leading and trailing quote from string, in Ruby

Question

I want to strip leading and trailing quotes, in Ruby, from a string. The quote character will occur 0 or 1 time. For example, all of the following should be converted to foo,bar:

• "foo,bar"
• "foo,bar
• foo,bar"
• foo,bar

Answer 1

I can use gsub to search for the leading or trailing quote and replace it with an empty string:

s = "\"foo,bar\""
s.gsub!(/^\"|\"?$/, '')

As suggested by comments below, a better solution is:

s.gsub!(/\A"|"\Z/, '')

Answer 2

As usual everyone grabs regex from the toolbox first. :-)

As an alternate I'll recommend looking into .tr('"', '') (AKA "translate") which, in this use, is really stripping the quotes.

Answer 3

You could also use the chomp function, but it unfortunately only works in the end of the string, assuming there was a reverse chomp, you could:

'"foo,bar"'.rchomp('"').chomp('"')

Implementing rchomp is straightforward:

class String
  def rchomp(sep = $/)
    self.start_with?(sep) ? self[sep.size..-1] : self
  end
end

Note that you could also do it inline, with the slightly less efficient version:

'"foo,bar"'.chomp('"').reverse.chomp('"').reverse