This feels like a terribly newbie question to be asking, but I'm stymied ...

I want to replace all single quotes in a string with backslask followed by a 
single quote.  The obvious approach doesn't seem to work, presumably because 
the replacement contains the pattern that's been replaced.

I assume there's an easy way to do this, but can't for the life of me think 
how.  Here's an example of the problem ...

irb(main):001:0> x="Don't say goodbye"
"Don't say goodbye"
irb(main):002:0> x
"Don't say goodbye"
irb(main):003:0> x.gsub("'", "\\'")
"Dont say goodbyet say goodbye"
irb(main):004:0>