Sha256: 0fdf698579775aeaf336debd8f598a0f22f6b8ffb317035cf4c1f3176ddac6d4
Contents?: true
Size: 1.2 KB
Versions: 8
Compression:
Stored size: 1.2 KB
Contents
module DataMapper
module Support
class WeakHash
attr_reader :cache
def initialize( cache = Hash.new )
@cache = cache
@key_map = {}
@rev_cache = Hash.new{|h,k| h[k] = {}}
@reclaim_value = lambda do |value_id|
if @rev_cache.has_key? value_id
@rev_cache[value_id].each_key{|key| @cache.delete key}
@rev_cache.delete value_id
end
end
@reclaim_key = lambda do |key_id|
if @key_map.has_key? key_id
@cache.delete @key_map[key_id]
end
end
end
def []( key )
value_id = @cache[key]
return ObjectSpace._id2ref(value_id) unless value_id.nil?
nil
rescue RangeError
nil
end
def []=( key, value )
case key
when Fixnum, Symbol, true, false
key2 = key
else
key2 = key.dup
end
@rev_cache[value.object_id][key2] = true
@cache[key2] = value.object_id
@key_map[key.object_id] = key2
ObjectSpace.define_finalizer(value, @reclaim_value)
ObjectSpace.define_finalizer(key, @reclaim_key)
end
end # class WeakHash
end # module Support
end # module DataMapper
Version data entries
8 entries across 8 versions & 1 rubygems