diff options
author | matz <matz@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2006-07-31 06:34:10 +0000 |
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committer | matz <matz@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2006-07-31 06:34:10 +0000 |
commit | 17c3d539f008c3ad4179e520511b6a64fb4ba969 (patch) | |
tree | 6a277eed8c128f9212b0ef8316750e697701059d /lib/weakref.rb | |
parent | dc136c12ee4d704de7621408ab0a5d9108284b45 (diff) |
* ruby.h: use ifdef (or defined) for macro constants that may or
may not be defined to shut up gcc's -Wundef warnings.
[ruby-core:08447]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8@10648 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'lib/weakref.rb')
-rw-r--r-- | lib/weakref.rb | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/lib/weakref.rb b/lib/weakref.rb index 49b907ba17..142286e765 100644 --- a/lib/weakref.rb +++ b/lib/weakref.rb @@ -1,4 +1,11 @@ -# Weak Reference class that does not bother GCing. + +require "delegate" + +# Weak Reference class that does not bother GCing. This allows the +# referenced object to be garbage collected as if nothing else is +# referring to it. Because Weakref inherits from Delegator it passes +# method calls to the object from which it was constructed, so it +# is of the same Duck Type. # # Usage: # foo = Object.new @@ -8,11 +15,9 @@ # p foo.to_s # should be same class # ObjectSpace.garbage_collect # p foo.to_s # should raise exception (recycled) - -require "delegate" - class WeakRef<Delegator + # RefError is raised if an object cannot be referenced by a WeakRef. class RefError<StandardError end @@ -40,6 +45,7 @@ class WeakRef<Delegator end } + # Create a new WeakRef from +orig+. def initialize(orig) super @__id = orig.__id__ @@ -56,6 +62,9 @@ class WeakRef<Delegator @@id_rev_map[self.__id__] = @__id end + # Return the object this WeakRef references. Raise + # RefError if this is impossible. The object is that + # to which method calls are delegated (see Delegator). def __getobj__ unless @@id_rev_map[self.__id__] == @__id raise RefError, "Illegal Reference - probably recycled", caller(2) @@ -67,6 +76,7 @@ class WeakRef<Delegator end end + # Determine if this Weakref still refers to anything. def weakref_alive? @@id_rev_map[self.__id__] == @__id end |