Task

Replace every occurring instance of a piece of text in a group of text files with another one.



For this task we want to replace the text   "Goodbye London!"   with   "Hello New York!"   for a list of files.




var names = %w(
                a.txt
                b.txt
                c.txt
              )
 
names.map{ File(_) }.each { |file|
    say file.edit { |line|
        line.gsub("Goodbye London!", "Hello New York!")
    }
}