Check out example codes for "A Ruby write to file example". It will help you in understanding the concepts better.

Code Example 1

# open and write to a file with ruby
open('myfile.out', 'w') do |f|
  f.puts "Hello, world."
end

# an alternative approach:
open('myfile.out', 'w') do |f|
  f << "Hello, world.\n"
end

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