CODEWITHSUNDEEP
rubymultithreading
sawa
sawa

Reputation: 168189

Adding code to an existing thread

Given a thread (that is not dead):

t = Thread.new{sleep}

is it possible to add some code, given as a proc for example, and run that within t?

Upvotes: 2

Views: 137

Answers (1)

Kimmo Lehto
Kimmo Lehto

Reputation: 6041

Perhaps by using a thread variable and waiting until it's defined:

a = Thread.new do
  while Thread.current["proc"].nil?
    sleep 0.5
    puts "Next round.."
  end
  Thread.current["proc"].call
end

sleep 3

a["proc"] = Proc.new { puts "hello there!" }

a.join

Which will output:

Next round..
Next round..
Next round..
Next round..
Next round..
Next round..
hello there!

But if you're asking if you can break the Thread.new {sleep} from sleeping and inserting something else for it to run, I don't know, maybe by using thread.raise :

class ExceptionWithProc < StandardError
  attr_accessor :proc
end

a = Thread.new {sleep rescue $!.proc.call}

exception = ExceptionWithProc.new
exception.proc = Proc.new { puts "hello there!" }

sleep 3

a.raise(exception)
a.join

Upvotes: 6

Related Questions