[ruby-core:31900] Re: Garbage Collection Question

On Fri, Aug 27, 2010 at 12:33 PM, Asher <[e-mail]> wrote:
> On Aug 27, 2010, at 12:09 PM, Evan Phoenix wrote:
>> It doesn't happen with every object allocated in a script body, only sometimes.
>
> No, it happens _every_ time. See examples.

Modified original program:

##################################################

weak_hash = Hash::Weak.new

class TestClass
end

1_000.times do |n|
  test_object = TestClass.new

  weak_hash[ n ] = test_object
  valid_key = weak_hash[ n ]
  p valid_key
end

class AnotherClass
end

test_object = nil

1_000.times do |n|
  print "getting test object (#{n}) (should fail with rb_eRangeError): "
  invalid_key = weak_hash[ n ]
  p invalid_key
  # error - returns valid key
end

##################################################

Output:

$ ruby -v gc.rb
ruby 1.8.7 (2010-01-10 patchlevel 249) [i486-linux]
#<TestClass:0xb73f6d64>
#<TestClass:0xb73f6d3c>
#<TestClass:0xb73f7e80>
[...]
#<TestClass:0xb73f7e30>
#<TestClass:0xb73f7e08>
#<TestClass:0xb73f7e80>
getting test object (0) (should fail with rb_eRangeError):
#<TestClass:0xb73f7e80>
getting test object (1) (should fail with rb_eRangeError):
#<TestClass:0xb73f7e80>
getting test object (2) (should fail with rb_eRangeError):
#<TestClass:0xb73f7e80>
[...]
getting test object (31) (should fail with rb_eRangeError):
#<TestClass:0xb73f7e80>
getting test object (32) (should fail with rb_eRangeError):
#<TestClass:0xb73f7e80>
gc.rb:15:in `_id2ref': 0xdb9fbf04 is recycled object (RangeError)
        from gc.rb:15:in `[]'
        from gc.rb:54
        from gc.rb:52:in `times'
        from gc.rb:52
getting test object (33) (should fail with rb_eRangeError):