call_block.print.rb

#!/usr/bin/env ruby

def runblock(foo)
  # fake data
  data = [1, 2, 3]
  if block_given?
    data.each { |v| yield(v) }
  end
  data
end

def printer(data)
   # like printrpc, but simpler
  puts "data has #{data.size} elements"
end

runblock('foo')

printer runblock('foo')


runblock('foo') do |value|
  puts value
end

printer runblock('foo') do |value|
  puts value
end

output

$ ruby call_block.print.rb
data has 3 elements
1
2
3
data has 3 elements