wrongly_cont_twice.lua

local eff = require('eff')
local inst, perform, handler = eff.inst, eff.perform, eff.handler

local Twice = inst()
local Exit = inst()

--[[
co = {
  print(1)
  coroutine.yield() -- *1
  corouitne.yield() -- *3
  print(2)
}

coroutine.resume(co) -- *2
coroutine.resume(co) -- *4
--]]

local h = handler {
  [Twice] = function(k)
    k() -- *2
    k() -- *4
  end,
  [Exit] = function() end,
  val = function() print("end") end
}

h(function()
  print(1)
  perform(Twice()) -- *1
  perform(Exit()) -- *3
  print(2)
end)

--[[
expected:
1

actual:
1
2
end
--]]