first commit

lib/knife/convoke.lua

@@ -0,0 +1,54 @@
+return function (routine)
+    local routines = { routine }
+    local routineIndex = 1
+    local isFinished = false
+
+    local function execute ()
+        local continueCount = 0
+        local run
+
+        local function continue ()
+            continueCount = continueCount + 1
+            return function (...)
+                continueCount = continueCount - 1
+                if continueCount == 0 then
+                    return run(...)
+                end
+            end
+        end
+
+        local function wait (...)
+            return coroutine.yield(...)
+        end
+
+        local r = coroutine.create(function ()
+            isFinished = false
+            while routineIndex <= #routines do
+                routines[routineIndex](continue, wait)
+                continueCount = 0
+                routineIndex = routineIndex + 1
+            end
+            isFinished = true
+        end)
+
+        run = function (...)
+            return coroutine.resume(r, ...)
+        end
+
+        run()
+    end
+
+    local function appendOrExecute (routine)
+        if routine then
+            routines[#routines + 1] = routine
+            if isFinished then
+                execute()
+            end
+            return appendOrExecute
+        else
+            execute()
+        end
+    end
+
+    return appendOrExecute
+end