class WeakRef(T)
Overview
Weak Reference class that allows a referenced object to be garbage-collected.
WARNING The referenced object cannot be a module.
NOTE To use WeakRef
, you must explicitly import it with require "weak_ref"
require "weak_ref"
ref = WeakRef.new("oof".reverse)
p ref # => #<WeakRef(String):0x7f83406eafa0 @target=Pointer(Void)@0x7f83406eafc0>
GC.collect
p ref # => #<WeakRef(String):0x7f83406eafa0 @target=Pointer(Void).null>
p ref.value # => nil
Note that the collection of objects is not deterministic, and depends on many subtle aspects. For instance,
if the example above is modified to print ref.value
in the first print, then the collector will not collect it.
Defined in:
weak_ref.crConstructors
Instance Method Summary
Instance methods inherited from class Reference
==(other : self)==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup, hash(hasher) hash, initialize initialize, inspect(io : IO) : Nil inspect, object_id : UInt64 object_id, pretty_print(pp) : Nil pretty_print, same?(other : Reference) : Bool
same?(other : Nil) same?, to_s(io : IO) : Nil to_s
Constructor methods inherited from class Reference
new
new,
unsafe_construct(address : Pointer, *args, **opts) : self
unsafe_construct
Class methods inherited from class Reference
pre_initialize(address : Pointer)
pre_initialize
Instance methods inherited from class Object
! : Bool
!,
!=(other)
!=,
!~(other)
!~,
==(other)
==,
===(other : JSON::Any)===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash(hasher)
hash hash, in?(collection : Object) : Bool
in?(*values : Object) : Bool in?, inspect(io : IO) : Nil
inspect : String inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil!(message)
not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO) : Nil
to_json : String to_json, to_pretty_json(indent : String = " ") : String
to_pretty_json(io : IO, indent : String = " ") : Nil to_pretty_json, to_s(io : IO) : Nil
to_s : String to_s, to_yaml(io : IO) : Nil
to_yaml : String to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as
Class methods inherited from class Object
from_json(string_or_io, root : String)from_json(string_or_io) from_json, from_yaml(string_or_io : String | IO) from_yaml