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instance method · added in Ruby 4.0

Ractor#value

() -> untyped

ractor.value → obj

# File tmp/rubies/ruby-4.1.0-preview1/ractor.rb, line 641
def value
  self.join
  __builtin_ractor_value
end

Waits for ractor to complete and returns its value or raises the exception which terminated the Ractor. The termination value will be moved to the calling Ractor. Therefore, at most 1 Ractor can receive another ractor’s termination value, and it can be received only once.

Example

r = Ractor.new{ [1, 2] }
r.value #=> [1, 2] (unshareable object)
r.value #=> Ractor::Error

Ractor.new(r){|r| r.value} #=> Ractor::Error

Ruby version changes

4.0
- Ractor#join and Ractor#value were added to wait for the termination of a Ractor. These are similar to Thread#join and Thread#value.