Few to_s improvements

Author: pitr-ch

lib/concurrent/atomic/atomic_fixnum.rb

@@ -129,5 +129,9 @@ module Concurrent
   #
   # @!macro atomic_fixnum_public_api
   class AtomicFixnum < AtomicFixnumImplementation
+    # @return [String] Short string representation.
+    def to_s
+      format '<#%s:0x%x value:%s>', self.class, object_id << 1, get
+    end
   end
 end

lib/concurrent/atomic/atomic_reference.rb

@@ -40,3 +40,10 @@ class Concurrent::AtomicReference < Concurrent::CAtomicReference
   class Concurrent::AtomicReference < Concurrent::MutexAtomicReference
   end
 end
+
+class Concurrent::AtomicReference
+  # @return [String] Short string representation.
+  def to_s
+    format '<#%s:0x%x value:%s>', self.class, object_id << 1, get
+  end
+end

lib/concurrent/edge/lock_free_stack.rb

@@ -113,5 +113,10 @@ def clear_each(&block)
         end
       end
     end
+
+    # @return [String] Short string representation.
+    def to_s
+      format '<#%s:0x%x %s>', self.class, object_id << 1, to_a.to_s
+    end
   end
 end