Feature #6694
openThread.new without block.
Description
Abstract¶
Support Thread.new() without block.
Before: Thread.new(params...){|thread_local_params| ...}
After: Thread.new(proc: lambda{|tl_params...| ...}, args: params..., other_thread_config...)
Background¶
Thread.new creates new Thread object and run passed block in another thread immediately. Thread.new can receive parameters and pass all parameters to block.
Thread.new(a, b, c) do |ta, tb, tc|
# ta, tb, tc is thread local
}
There are some request to specify thread configurations such as stack size described in [Ruby 1.9 - Feature #3187] (in this case, stack size for Fiber.new). However, we have no way to pass such thread configuration on the Thread.new().
Proposal¶
Allow Thread.new() without block. A block will be passed with proc parameter. Passed arguments will be passed with args parameter.
# ex1
Thread.new(){...}
#=>
Thread.new(proc: -> {...})
# ex2
Thread.new(a, b, c){|ta, tb, tc| ...}
#=>
Thread.new(proc: ->(ta, tb, tc){ ... }, params: [a, b, c])
If you want to specify stack size, then:
Thread.new(stack_size: 4096, proc: proc{...}, args: [a, b, c])
Note that I'll make another ticket for thread (and fiber) creation parameters.
This change can be described with the following pseudo code:
def Thread.new(*args, &block)
if block
Thread.new_orig(*args, &block)
else
config = args[0] || raise ArgumentError
stack_size = config[:stack_size]
# ... and process another parameters
Thread.new_orig(*config[:args], &config[:proc])
end
end
Another proposal¶
On the [ruby-core:43385], Nahi-san proposed that if no block given on Thread.new(), then create "waiting" thread. Thread#run kicks waiting thread with parameters.
th = Thread.new(thread_config_params)
...
th.run(params){|thread_local_params|
...
}
We can combine with proc:
parameter and this proposal.
If Thread.new()
doesn't have block and proc:
parameter, then making a waiting thread.
NOTE: Because we have already Thread#run, Thread#start is better than Thread#run?
Note¶
I don't make any survey on other languages. Please give us your comments.