Why does File.each work but File.readline doesn't?

Question

Why does File.each work but File.readline doesn't?

File.open('store-sample','r') do |f|

  f.readline("\n\n\n\n") do |l|
    binding.pry

  end
end

The code doesn't break however the following code works:

File.open('store-sample','r').each("\n\n\n\n") do |l|
  binding.pry
end

I don't know the internal implementation of these two methods, but this weird behavior really makes me crazy.

Answer 1

Why don't you use File.foreach? It's designed to return a single line at a time.

Answer 2

readline doesn’t take a block; it returns a value.

line = f.readline('\n\n\n\n')
# do something with line