Ruby: Unindent arbitrarily-indented heredocs

unindent_heredoc.rb

# Ruby: Unindent arbitrarily-indented heredocs
# 
# "Cowboy" Ben Alman
# http://benalman.com/

class String
  def unindent
    arr = respond_to?(:lines) ? lines : self
    min = arr.map {|line| line =~ /^(\s*)\S/; $1 && $1.length }.compact.min
    arr.map {|line| line.sub(/^\s{#{min}}/, '')}.join
  end
end

See the working example.