1 files changed, 43 insertions, 54 deletions
diff --git a/lib/weakref.rb b/lib/weakref.rb
index 93b2c65ecd..c7274f9664 100644
--- a/lib/weakref.rb
+++ b/lib/weakref.rb
@@ -1,70 +1,59 @@
-# Weak Reference class that does not bother GCing.
+# frozen_string_literal: true
+require "delegate"
+
+# Weak Reference class that allows a referenced object to be
+# garbage-collected.
+#
+# A WeakRef may be used exactly like the object it references.
 #
 # Usage:
-#   foo = Object.new
-#   foo.hash
-#   foo = WeakRef.new(foo)
-#   foo.hash
-#   ObjectSpace.garbage_collect
-#   foo.hash	# => Raises WeakRef::RefError (because original GC'ed)
+#
+#   foo = Object.new            # create a new object instance
+#   p foo.to_s                  # original's class
+#   foo = WeakRef.new(foo)      # reassign foo with WeakRef instance
+#   p foo.to_s                  # should be same class
+#   GC.start                    # start the garbage collector
+#   p foo.to_s                  # should raise exception (recycled)
+#
 
-require "delegate"
+class WeakRef < Delegator
+  # The version string
+  VERSION = "0.1.4"
+
+  ##
+  # RefError is raised when a referenced object has been recycled by the
+  # garbage collector
+
+  class RefError < StandardError
+  end
 
-class WeakRef<Delegater
+  @@__map = ::ObjectSpace::WeakMap.new
 
-  Exception :RefError
+  ##
+  # Creates a weak reference to +orig+
 
-  ID_MAP =  {}
-  ID_REV_MAP =  {}
-  ObjectSpace.add_finalizer(lambda{|id|
-			      rid = ID_MAP[id]
-			      if rid
-				ID_REV_MAP[rid] = nil
-				ID_MAP[id] = nil
-			      end
-			      rid = ID_REV_MAP[id]
-			      if rid
-				ID_REV_MAP[id] = nil
-				ID_MAP[rid] = nil
-			      end
-			    })
-			    
   def initialize(orig)
+    case orig
+    when true, false, nil
+      @delegate_sd_obj = orig
+    else
+      @@__map[self] = orig
+    end
     super
-    @id = orig.id
-    ObjectSpace.call_finalizer orig
-    ID_MAP[@id] = self.id
-    ID_REV_MAP[self.id] = @id
   end
 
-  def __getobj__
-    unless ID_MAP[@id]
-      $@ = caller(1)
-      $! = RefError.new("Illegal Reference - probably recycled")
-      raise
-    end
-    ObjectSpace.id2ref(@id)
-#    ObjectSpace.each_object do |obj|
-#      return obj if obj.id == @id
-#    end
+  def __getobj__(&_block) # :nodoc:
+    @@__map[self] or defined?(@delegate_sd_obj) ? @delegate_sd_obj :
+      Kernel::raise(RefError, "Invalid Reference - probably recycled", Kernel::caller(2))
   end
 
-  def weakref_alive?
-    if ID_MAP[@id]
-      true
-    else
-      false
-    end
+  def __setobj__(obj) # :nodoc:
   end
 
-  def []
-    __getobj__
+  ##
+  # Returns true if the referenced object is still alive.
+
+  def weakref_alive?
+    @@__map.key?(self) or defined?(@delegate_sd_obj)
   end
 end
-
-foo = Object.new
-p foo.hash
-foo = WeakRef.new(foo)
-p foo.hash
-ObjectSpace.garbage_collect
-p foo.hash