src/maps.luau

@@ -109,16 +109,12 @@ local function indexes<K, VI, VO>(input: () -> Map<K, VI>, transform: (() -> VI,
         return output_array
     end
 
-    local output = create_node(false :: any)
+    local output = create_node(false :: any, function()
-    output.effect = function()
         return update_children(input())
-    end
+    end)
 
-    open_scope(output)
+    evaluate_node(output)
 
-    output.cache = update_children(input())
-
-    close_scope()
 
     return function()
         track(output)
@@ -126,7 +122,6 @@ local function indexes<K, VI, VO>(input: () -> Map<K, VI>, transform: (() -> VI,
     end
 end
 
--- todo: optimize output array
 local function values<K, VI, VO>(input: () -> Map<K, VI>, transform: (VI, () -> K) -> VO): () -> { VO }
     local owner = get_scope()
     if not owner then
@@ -211,16 +206,11 @@ local function values<K, VI, VO>(input: () -> Map<K, VI>, transform: (VI, () ->
         return output_array
     end
 
-    local output = create_node(false :: any)
+    local output = create_node(false :: any, function()
-    output.effect = function()
         return update_children(input())
-    end
+    end)
 
-    open_scope(output)
+    evaluate_node(output)
-
-    output.cache = update_children(input())
-
-    close_scope()
 
     return function()
         track(output)

test/benchmark.luau

@@ -73,7 +73,7 @@ BENCH("set derived value", function()
     local src = vide.source(1)
 
     vide.root(function()
-        local _derived = vide.derive(src)
+        local _derived = vide.derive(function() return src() end)
 
         for i = 1, START(N) do
             src(i)

test/tests.luau

@@ -399,7 +399,7 @@ TEST("derive()", wrap_root(function()
 
         local count = 0
 
-        effect(function() c() count += 1 end)
+        effect(function() c(); count += 1 end)
 
         b(true)
         CHECK(c() == "b")
@@ -453,11 +453,28 @@ TEST("derive()", wrap_root(function()
         gc()
         CHECK(wref[1])
     end
+
+    do CASE "raw derive"
+        local a = source(1)
+        local b = derive(a)
+
+        local count = 0
+    
+        effect(function()
+            b()
+            count += 1
+        end)
+
+        CHECK(count == 1)
+        a(2)
+        CHECK(count == 2)
+    end
 end))
 
 TEST("effect()", wrap_root(function()
     local source = vide.source
     local effect = vide.effect
+    local derive = vide.derive
 
     do CASE "rerun on source change"
         local a = source(1)
@@ -476,6 +493,38 @@ TEST("effect()", wrap_root(function()
         b(2)
         CHECK(count == 3)
     end
+
+    do CASE "rerun on derived source change"
+        local num = source(0)
+
+        local text = derive(function() return tostring(num()) end)
+        
+        local count = 0
+        effect(function()
+            text()
+            count += 1
+        end)
+
+        num(1)
+
+        CHECK(count == 2)
+    end
+
+    do CASE "cache"
+        local num = source(0)
+
+        local count
+
+        effect(function(x: number)
+            num()
+            count = x + 1
+            return x + 1
+        end, 0)
+
+        num(1)
+
+        CHECK(count == 2)
+    end
 end))
 
 TEST("cleanup()", wrap_root(function()