Ruby regex gsub a line in a text file

Question

I need to match a line in an inputted text file string and wrap that captured line with a character for example.

For example imagine a text file as such:

<         


        

Answer 1

If you're trying to match every line, then

gsub(/^.*$/, 'X\&X')

does the trick. If you only want to match certain lines, then replace .* with whatever you need.

Update:

Replacing your gsub with mine:

string = IO.read(ARGV[0])
string = string.gsub(/^.*$/, 'X\&X')
puts string

I get:

$ gsub.rb testfile
XtestX
XfooX
XtestX
XbarX

Update 2:

As per @CodeGnome, you might try adding chomp:

IO.readlines(ARGV[0]).each do |line|
  puts "X#{line.chomp}X"
end

This works equally well for me. My understanding of ^ and $ in regular expressions was that chomping wouldn't be necessary, but maybe I'm wrong.