Add func.for_generator

func.lua

@@ -1,5 +1,6 @@
 -- Localize globals
-local error, modlib, unpack = error, modlib, unpack
+local error, coroutine, modlib, unpack
+	= error, coroutine, modlib, unpack
 
 -- Set environment
 local _ENV = {}
@@ -47,6 +48,27 @@ function iterate(callback, iterator, ...)
 	return _iterate(iterator(...))
 end
 
+function for_generator(caller, ...)
+	local co = coroutine.create(function(...)
+		return caller(function(...)
+			return coroutine.yield(...)
+		end, ...)
+	end)
+	local args = {...}
+	return function()
+		if coroutine.status(co) == "dead" then
+			return
+		end
+		local function _iterate(status, ...)
+			if not status then
+				error((...))
+			end
+			return ...
+		end
+		return _iterate(coroutine.resume(co, unpack(args)))
+	end
+end
+
 -- Does not use select magic, stops at the first nil value
 function aggregate(binary_func, total, ...)
 	if total == nil then return end

test.lua

@@ -19,10 +19,22 @@ setfenv(1, setmetatable({}, {
 -- func
 do
 	local tab = {a = 1, b = 2}
-	func.iterate(function(key, value)
+	local function check_entry(key, value)
 		assert(tab[key] == value)
 		tab[key] = nil
-	end, pairs, tab)
+	end
+	func.iterate(check_entry, pairs, tab)
+	assert(next(tab) == nil)
+
+	tab = {a = 1, b = 2}
+	local function pairs_callback(callback, tab)
+		for k, v in pairs(tab) do
+			callback(k, v)
+		end
+	end
+	for k, v in func.for_generator(pairs_callback, tab) do
+		check_entry(k, v)
+	end
 	assert(next(tab) == nil)
 	assert(func.aggregate(func.add, 1, 2, 3) == 6)
 end