symbol-gc.rb

symbol-gc.rb

puts "Ruby version: #{RUBY_VERSION}"

def show_a_sym(sym)
  puts "sym #{sym} = #{sym.object_id}"
end

def pick_a_sym
  a = (1..100_000).map{|s| :"dummy-#{s}" }
  sym = a.sample
  show_a_sym sym 
  sym.to_s.gsub(/dummy-/, '').to_i
end

def make_a_sym(i)
  show_a_sym :"dummy-#{i}"
end

i = pick_a_sym

make_a_sym i

GC.start

make_a_sym i

Garbage-collected symbols get new object IDs in Ruby 2.2.

Ruby version: 2.2.1
sym dummy-23284 = 14517920
sym dummy-23284 = 14517920
sym dummy-23284 = 9494360