How to replace multiple newlines in a row with one newline using Ruby

Question

I have a script written in ruby. I need to remove any duplicate newlines (e.g.)

\\n
\\n
\\n

to

\\n

My current

Answer 1

This works for me:

#!/usr/bin/ruby

$s = "foo\n\n\nbar\nbaz\n\n\nquux";

puts $s

$s.gsub!(/[\n]+/, "\n");

puts $s

Answer 2

You need to match more than one newline up to an infinite amount. Your code example will work with just a minor tweak:

str.gsub!(/\n+/, "\n")

For example:

str = "this\n\n\nis\n\n\n\n\na\ntest"
str.gsub!(/\n+/, "\n")  # => "this\nis\na\ntest"

Answer 3

Ruby needs the backslashes escaped differently than you have provided.

str.sub!("\\\\n+\\\\n","\\\\n")

http://www.ruby-forum.com/topic/176239