Equivalent to +File::open+ with an associated block, but moves any existing file with the same name to the side first.
# File lib/inline.rb, line 839 def self.write_with_backup(path) # returns true if file already existed # move previous version to the side if it exists renamed = false if test ff, path then renamed = true File.rename path, path + ".old" end File.open(path, "w") do |io| yield(io) end return renamed end