Why do I have to specify the name of the module when code is included in remote processes?

General Usage
,
1

Hi

Consider the following two files test.jl and temp.jl with the following content

# test.jl file 

module Foo

using Distributed
function baz()
    addprocs(2)
    @everywhere include("temp.jl")
    for worker in workers()
        remotecall_fetch(println, worker, bar)
    end
end

function baz2()
    addprocs(2)
    @everywhere include("temp.jl")
    for worker in workers()
        remotecall_fetch(println, worker, Main.bar)
    end
end

end # module 

# temp.jl
bar(x) = 2x

When I run the following

julia> import .Foo

julia> using Distributed

julia> @fetchfrom workers()[1] InteractiveUtils.varinfo() # bar is in varinfo
  name             size summary                             
  ––––––––––– ––––––––– ––––––––––––––––––––––––––––––––––––
  Base                  Module                              
  Core                  Module                              
  Distributed 1.079 MiB Module                              
  Main                  Module                              
  bar           0 bytes bar (generic function with 1 method)

I see that bar is loaded in the worker process. While the following throws an UndefVarError

julia> Foo.baz() 
ERROR: UndefVarError: bar not defined
Stacktrace:
 [1] baz()
   @ Main.Foo ~/.julia/dev/DynamicalNetworks/ClusterShiftKeyinChaosCommunication/test.jl:22
 [2] top-level scope
   @ REPL[1]:1

the following throws no error.

julia> Foo.baz2()
      From worker 2:    bar
      From worker 3:    bar
      From worker 4:    bar
      From worker 5:    bar
      From worker 6:    bar
      From worker 7:    bar

Thus, it seems that bar cannot be used without specifying the module name Main explicitly. I understand that bar is bound to module Main. But, why do I have to specify it when I try to reach the bound function bar?

Moreover, if I define function not inside of a module, the prefix Main is not required again as shown below. I could not get why. Any help is appreciated.

julia> function baz3()
           addprocs(2)
           @everywhere include("temp.jl")
           for worker in workers()
               remotecall_fetch(println, worker, bar)
           end
       end
baz3 (generic function with 1 method)

julia> baz3()
      From worker 2:    bar
      From worker 3:    bar
      From worker 4:    bar
      From worker 5:    bar
      From worker 6:    bar