now able to return funcs

Author: ms-jpq

README.md

@@ -4,6 +4,11 @@ Async Await in [90 lines](https://github.com/ms-jpq/neovim-async-tutorial/blob/m
 
 ## Preface
 
+### Special Thanks
+
+[svermeulen](https://github.com/svermeulen) for fixing [inability to return functions](https://github.com/ms-jpq/neovim-async-tutorial/issues/2).
+
+
 This tutorial assumes that you are familiar with the concept of `async` `await`
 
 You will also need to read through the [first 500 words](https://www.lua.org/pil/9.1.html) of how coroutines work in lua.

lua/async.lua

@@ -11,13 +11,13 @@ local pong = function (func, callback)
   local thread = co.create(func)
   local step = nil
   step = function (...)
-    local go, ret = co.resume(thread, ...)
-    if not go then
-      assert(co.status(thread) == "suspended", ret)
-    elseif type(ret) == "function" then
-      ret(step)
-    else
+    local stat, ret = co.resume(thread, ...)
+    assert(stat, ret)
+    if co.status(thread) == "dead" then
       (callback or function () end)(ret)
+    else
+      assert(type(ret) == "function", "type error :: expected func")
+      ret(step)
     end
   end
   step()
@@ -84,4 +84,3 @@ return {
   wait_all = await_all,
   wrap = wrap,
 }
-

lua/tutorial.lua

@@ -72,13 +72,16 @@ local async_tasks_1 = function()
   end)
 end
 
+
 local async_tasks_2 = function (val)
   return a.sync(function ()
     -- await all
     local w, z = a.wait_all{e2(val, val + 1), e2(val + 2, val + 3)}
     print(unpack(w))
     print(unpack(z))
-    return 4
+    return function ()
+      return 4
+    end
   end)
 end
 
@@ -88,7 +91,7 @@ local async_example = function ()
     -- composable, await other async thunks
     local u = a.wait(async_tasks_1())
     local v = a.wait(async_tasks_2(3))
-    print(u + v)
+    print(u + v())
   end)
 end