async_await.lua

   1 lua_async.async_await = {}
   2
   3 function lua_async.resume(co)
   4         local status, err = coroutine.resume(co)
   5
   6         if coroutine.status(co) == "dead" or err then
   7                 lua_async.limiting.unset_limit(co)
   8         end
   9
  10         if not status then
  11                 error("Error (in async function): " .. err)
  12         end
  13 end
  14
  15 function await(promise)
  16         local co = assert(coroutine.running(), "await called outside of an async function")
  17
  18         if promise.state == "pending" then
  19                 promise:then_(function()
  20                         lua_async.resume(co)
  21                 end)
  22
  23                 coroutine.yield()
  24         end
  25
  26         return unpack(promise.values)
  27 end
  28
  29 function async(func)
  30         return function(...)
  31                 local promise = Promise()
  32                 promise.__on_resolve = func
  33
  34                 local args = {...}
  35
  36                 lua_async.resume(coroutine.create(function()
  37                         promise:resolve(unpack(args))
  38                 end))
  39
  40                 return promise
  41         end
  42 end
  43