Sha256: 72a7d0ca36240e7160f783eed1fdd1c09c0f68451d3bb859aff45bc5c932af81
Contents?: true
Size: 1.17 KB
Versions: 16
Compression:
Stored size: 1.17 KB
Contents
module Swift
# Weak hash set.
#--
# TODO: Is 'hash set' the real name for a hash where both the keys and values must be unique?
class IdentityMap
def initialize
@cache, @reverse_cache, @finalize = {}, {}, method(:finalize)
end
def get key
value_id = @cache[key]
return ObjectSpace._id2ref(value_id) unless value_id.nil?
nil
end
#--
# TODO: Barf if the value.object_id already exists in the cache.
def set key, value
@reverse_cache[value.object_id] = key
@cache[key] = value.object_id
ObjectSpace.define_finalizer(value, @finalize)
end
private
def finalize value_id
@cache.delete @reverse_cache.delete value_id
end
end # IdentityMap
class Adapter
def identity_map
@identity_map ||= IdentityMap.new
end
end
class Scheme
#--
# TODO: Redefined method :(
def self.load tuple
im = [self, *tuple.values_at(*header.keys)]
unless scheme = Swift.db.identity_map.get(im)
scheme = allocate
scheme.tuple = tuple
Swift.db.identity_map.set(im, scheme)
end
scheme
end
end # Scheme
end # Swift
Version data entries
16 entries across 16 versions & 1 rubygems