rf-web/vendor/bundle/gems/concurrent-ruby-1.1.5/lib/concurrent/settable_struct.rb
2019-10-21 10:18:17 +02:00

130 lines
3.8 KiB
Ruby

require 'concurrent/synchronization/abstract_struct'
require 'concurrent/errors'
require 'concurrent/synchronization'
module Concurrent
# An thread-safe, write-once variation of Ruby's standard `Struct`.
# Each member can have its value set at most once, either at construction
# or any time thereafter. Attempting to assign a value to a member
# that has already been set will result in a `Concurrent::ImmutabilityError`.
#
# @see http://ruby-doc.org/core-2.2.0/Struct.html Ruby standard library `Struct`
# @see http://en.wikipedia.org/wiki/Final_(Java) Java `final` keyword
module SettableStruct
include Synchronization::AbstractStruct
# @!macro struct_values
def values
synchronize { ns_values }
end
alias_method :to_a, :values
# @!macro struct_values_at
def values_at(*indexes)
synchronize { ns_values_at(indexes) }
end
# @!macro struct_inspect
def inspect
synchronize { ns_inspect }
end
alias_method :to_s, :inspect
# @!macro struct_merge
def merge(other, &block)
synchronize { ns_merge(other, &block) }
end
# @!macro struct_to_h
def to_h
synchronize { ns_to_h }
end
# @!macro struct_get
def [](member)
synchronize { ns_get(member) }
end
# @!macro struct_equality
def ==(other)
synchronize { ns_equality(other) }
end
# @!macro struct_each
def each(&block)
return enum_for(:each) unless block_given?
synchronize { ns_each(&block) }
end
# @!macro struct_each_pair
def each_pair(&block)
return enum_for(:each_pair) unless block_given?
synchronize { ns_each_pair(&block) }
end
# @!macro struct_select
def select(&block)
return enum_for(:select) unless block_given?
synchronize { ns_select(&block) }
end
# @!macro struct_set
#
# @raise [Concurrent::ImmutabilityError] if the given member has already been set
def []=(member, value)
if member.is_a? Integer
length = synchronize { @values.length }
if member >= length
raise IndexError.new("offset #{member} too large for struct(size:#{length})")
end
synchronize do
unless @values[member].nil?
raise Concurrent::ImmutabilityError.new('struct member has already been set')
end
@values[member] = value
end
else
send("#{member}=", value)
end
rescue NoMethodError
raise NameError.new("no member '#{member}' in struct")
end
# @!macro struct_new
def self.new(*args, &block)
clazz_name = nil
if args.length == 0
raise ArgumentError.new('wrong number of arguments (0 for 1+)')
elsif args.length > 0 && args.first.is_a?(String)
clazz_name = args.shift
end
FACTORY.define_struct(clazz_name, args, &block)
end
FACTORY = Class.new(Synchronization::LockableObject) do
def define_struct(name, members, &block)
synchronize do
clazz = Synchronization::AbstractStruct.define_struct_class(SettableStruct, Synchronization::LockableObject, name, members, &block)
members.each_with_index do |member, index|
clazz.send :remove_method, member if clazz.instance_methods.include? member
clazz.send(:define_method, member) do
synchronize { @values[index] }
end
clazz.send(:define_method, "#{member}=") do |value|
synchronize do
unless @values[index].nil?
raise Concurrent::ImmutabilityError.new('struct member has already been set')
end
@values[index] = value
end
end
end
clazz
end
end
end.new
private_constant :FACTORY
end
end