wip(0.S3): ui blocks, scene on enter/exit, hooks, machines over a state's field, namespace and engine-system injection; a reference out of a read-only state or a module let is read-only; deps counts writes into another module's state; the rejected examples hold states

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

examples/rejected/fn_type_mismatch.ludic

@@ -1,6 +1,8 @@
 # fn_type_mismatch.ludic - a function of one type where another is wanted is refused, by name
 program FnTypeMismatch {
   function half(x: float) -> float { return x / 2.0 }
-  var op: fn(int) -> int = null
-  entry { op = fn half }
+  state Ops {
+    op: fn(int) -> int = null
+  }
+  entry (ops: mut Ops) { ops.op = fn half }
 }

examples/rejected/friend_scope.ludic

@@ -3,8 +3,8 @@ import "private_bank"
 import "private_kit"
 program FriendScope {
   friend module lab of kit
-  entry {
-    add(5)
-    print(total())
+  entry (bank_st: mut BankState) {
+    add(bank_st, 5)
+    print(total(bank_st))
   }
 }

examples/rejected/port_var_args.ludic

@@ -1,8 +1,8 @@
-# L3: a variable answers a member that takes nothing; price takes an int, so it binds a function
+# L3: a state's field answers a member that takes nothing; price takes an int, so it binds a function
 program PortVarArgs {
   port Purse { price: fn(int) -> int }
-  var g_rate: int = 3
-  bind Purse { price: g_rate }
+  state Rates { rate: int = 3 }
+  bind Purse { price: Rates.rate }
   entry {
     print(Purse.price(2))
   }

examples/rejected/private_bank/ledger.ludic

@@ -1,13 +1,15 @@
 # bank/ledger.ludic - inherits `module bank` from the barrel that imports it
-var balance: int = 0
-export event Deposited { amount: int }
-function add(n: int) -> void {
-  balance += n
+export state BankState {
+  balance: int = 0
 }
-export function deposit(n: int) -> void {
-  add(n)
+export event Deposited { amount: int }
+function add(bank_st: mut BankState, n: int) -> void {
+  bank_st.balance += n
+}
+export function deposit(bank_st: mut BankState, n: int) -> void {
+  add(bank_st, n)
   emit Deposited(amount: n)
 }
-export function total() -> int {
-  return balance
+export function total(bank_st: BankState) -> int {
+  return bank_st.balance
 }

examples/rejected/private_module.ludic

@@ -1,8 +1,8 @@
 # L3: `add` is private to module bank; calling it from outside the module is refused
 import "private_bank"
 program Private {
-  entry {
-    add(5)
-    print(total())
+  entry (bank_st: mut BankState) {
+    add(bank_st, 5)
+    print(total(bank_st))
   }
 }

examples/rejected/uses_pkg_mech/index.ludic

@@ -4,5 +4,5 @@ module mech uses ludic_base
 import "ludic.base"
 import "ludic.inventory"
 export function stock() -> int {
-  return inv_count(0)
+  return inv_limit(0)
 }

examples/rejected/view_untyped.ludic

@@ -1,9 +1,9 @@
-# a view field that is not a bare global has to say its type
+# a view field that is not a bare field of its state has to say its type
 import "ludic.ui"
 program ViewUntyped {
-  var a: int = 1
-  view Sums {
-    total = a + 2
+  state Nums { a: int = 1 }
+  view Sums (n: Nums) {
+    total = n.a + 2
   }
-  entry { print(view_sums().name) }
+  entry { print(1) }
 }

examples/rejected/view_without_ui.ludic

@@ -1,8 +1,8 @@
 # a view is for templates, which ludic.ui shows
 program ViewWithoutUi {
-  var a: int = 1
-  view Sums {
-    a = a
+  state Nums { a: int = 1 }
+  view Sums (n: Nums) {
+    a: int = n.a
   }
-  entry { print(a) }
+  entry { print(1) }
 }