Blocks

blocks.rb

def fibonacci_up_to(number)
  i1, i2 = 1, 1
  while i1 <= number
    yield i1
    i1, i2 = i2, i1+i2
  end
end

fibonacci_up_to(40){|fib| puts fib}

def triangle_up_to(number)
  i, k = 1, 1
  while i <= number
    yield i
    k += 1
    i += k
  end
end

triangle_up_to(100){|tr| puts tr}

require "mathn"

Prime.new.each{|p| puts p; break if p > 100}

def word_counter(word)
  words_array = word.scan /[\w'^"]+/
  words_hash = Hash.new(0)
  words_array.each do |word|
    words_hash[word] += 1
  end
  words_hash.each{|word, count| yield word, count}
end
word_counter("a a a a b b b"){|word, counter| puts "The word '#{word}' appears #{counter} times"}