Chapter 14 is WASM friendly.

Cargo.lock

@@ -306,6 +306,8 @@ dependencies = [
  "serde_json 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)",
  "specs 0.15.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "specs-derive 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "wasm-bindgen 0.2.50 (registry+https://github.com/rust-lang/crates.io-index)",
+ "web-sys 0.3.27 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]

book/src/chapter_14.md

@@ -567,20 +567,30 @@ impl<'a> System<'a> for ItemRemoveSystem {
 Lastly, we add it to the systems in `main.rs`:
 
 ```rust
-let mut gs = State {
-    ecs: World::new(),
-    systems : DispatcherBuilder::new()
-        .with(MapIndexingSystem{}, "map_indexing_system", &[])
-        .with(VisibilitySystem{}, "visibility_system", &[])
-        .with(MonsterAI{}, "monster_ai", &["visibility_system", "map_indexing_system"])
-        .with(MeleeCombatSystem{}, "melee_combat", &["monster_ai"])
-        .with(DamageSystem{}, "damage", &["melee_combat"])
-        .with(ItemCollectionSystem{}, "pickup", &["melee_combat"])
-        .with(ItemUseSystem{}, "potions", &["melee_combat"])
-        .with(ItemDropSystem{}, "drop_items", &["melee_combat"])
-        .with(ItemRemoveSystem{}, "remove_items", &["melee_combat"])
-        .build(),
-};
+impl State {
+    fn run_systems(&mut self) {
+        let mut mapindex = MapIndexingSystem{};
+        mapindex.run_now(&self.ecs);
+        let mut vis = VisibilitySystem{};
+        vis.run_now(&self.ecs);
+        let mut mob = MonsterAI{};
+        mob.run_now(&self.ecs);
+        let mut melee = MeleeCombatSystem{};
+        melee.run_now(&self.ecs);
+        let mut damage = DamageSystem{};
+        damage.run_now(&self.ecs);
+        let mut pickup = ItemCollectionSystem{};
+        pickup.run_now(&self.ecs);
+        let mut itemuse = ItemUseSystem{};
+        itemuse.run_now(&self.ecs);
+        let mut drop_items = ItemDropSystem{};
+        drop_items.run_now(&self.ecs);
+        let mut item_remove = ItemRemoveSystem{};
+        item_remove.run_now(&self.ecs);
+
+        self.ecs.maintain();
+    }
+}
 ```
 
 Now if you `cargo run`, you can pick up a dagger or shield and equip it. Then you can press `R` to remove it.

chapter-14-gear/Cargo.toml

@@ -12,3 +12,7 @@ specs = { version = "0.15.0", features = ["serde"] }
 specs-derive = "0.4.0"
 serde= { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
+
+[target.'cfg(any(target_arch = "wasm32"))'.dependencies]
+web-sys = { version = "0.3", features=["console"] }
+wasm-bindgen = "0.2"

chapter-14-gear/src/main.rs

@@ -32,6 +32,8 @@ use inventory_system::{ ItemCollectionSystem, ItemUseSystem, ItemDropSystem, Ite
 pub mod saveload_system;
 pub mod random_table;
 
+rltk::add_wasm_support!();
+
 #[derive(PartialEq, Copy, Clone)]
 pub enum RunState { AwaitingInput, 
     PreRun, 
@@ -48,8 +50,32 @@ pub enum RunState { AwaitingInput,
 }
 
 pub struct State {
-    pub ecs: World,
-    pub systems: Dispatcher<'static, 'static>
+    pub ecs: World
+}
+
+impl State {
+    fn run_systems(&mut self) {
+        let mut mapindex = MapIndexingSystem{};
+        mapindex.run_now(&self.ecs);
+        let mut vis = VisibilitySystem{};
+        vis.run_now(&self.ecs);
+        let mut mob = MonsterAI{};
+        mob.run_now(&self.ecs);
+        let mut melee = MeleeCombatSystem{};
+        melee.run_now(&self.ecs);
+        let mut damage = DamageSystem{};
+        damage.run_now(&self.ecs);
+        let mut pickup = ItemCollectionSystem{};
+        pickup.run_now(&self.ecs);
+        let mut itemuse = ItemUseSystem{};
+        itemuse.run_now(&self.ecs);
+        let mut drop_items = ItemDropSystem{};
+        drop_items.run_now(&self.ecs);
+        let mut item_remove = ItemRemoveSystem{};
+        item_remove.run_now(&self.ecs);
+
+        self.ecs.maintain();
+    }
 }
 
 impl GameState for State {
@@ -87,7 +113,7 @@ impl GameState for State {
         
         match newrunstate {
             RunState::PreRun => {
-                self.systems.dispatch(&self.ecs);
+                self.run_systems();
                 self.ecs.maintain();
                 newrunstate = RunState::AwaitingInput;
             }
@@ -95,12 +121,12 @@ impl GameState for State {
                 newrunstate = player_input(self, ctx);
             }
             RunState::PlayerTurn => {
-                self.systems.dispatch(&self.ecs);
+                self.run_systems();
                 self.ecs.maintain();
                 newrunstate = RunState::MonsterTurn;
             }
             RunState::MonsterTurn => {
-                self.systems.dispatch(&self.ecs);
+                self.run_systems();
                 self.ecs.maintain();
                 newrunstate = RunState::AwaitingInput;
             }
@@ -345,21 +371,10 @@ impl State {
 }
 
 fn main() {
-    let mut context = Rltk::init_simple8x8(80, 50, "Hello Rust World", "../resources");
+    let mut context = Rltk::init_simple8x8(80, 50, "Hello Rust World", "resources");
     context.with_post_scanlines(true);
     let mut gs = State {
-        ecs: World::new(),
-        systems : DispatcherBuilder::new()
-            .with(MapIndexingSystem{}, "map_indexing_system", &[])
-            .with(VisibilitySystem{}, "visibility_system", &[])
-            .with(MonsterAI{}, "monster_ai", &["visibility_system", "map_indexing_system"])
-            .with(MeleeCombatSystem{}, "melee_combat", &["monster_ai"])
-            .with(DamageSystem{}, "damage", &["melee_combat"])
-            .with(ItemCollectionSystem{}, "pickup", &["melee_combat"])
-            .with(ItemUseSystem{}, "potions", &["melee_combat"])
-            .with(ItemDropSystem{}, "drop_items", &["melee_combat"])
-            .with(ItemRemoveSystem{}, "remove_items", &["melee_combat"])
-            .build(),
+        ecs: World::new()
     };
     gs.ecs.register::<Position>();
     gs.ecs.register::<Renderable>();

chapter-14-gear/src/saveload_system.rs

@@ -20,6 +20,11 @@ macro_rules! serialize_individually {
     };
 }
 
+#[cfg(target_arch = "wasm32")]
+pub fn save_game(_ecs : &mut World) {
+}
+
+#[cfg(not(target_arch = "wasm32"))]
 pub fn save_game(ecs : &mut World) {
     // Create helper
     let mapcopy = ecs.get_mut::<super::map::Map>().unwrap().clone();
@@ -56,7 +61,7 @@ macro_rules! deserialize_individually {
         $(
         DeserializeComponents::<NoError, _>::deserialize(
             &mut ( &mut $ecs.write_storage::<$type>(), ),
-            &mut $data.0, // entities
+            &$data.0, // entities
             &mut $data.1, // marker
             &mut $data.2, // allocater
             &mut $de,

wasmbuild.bat

@@ -13,6 +13,7 @@ CALL :Stage chapter-10-ranged
 CALL :Stage chapter-11-loadsave
 CALL :Stage chapter-12-delvingdeeper
 CALL :Stage chapter-13-difficulty
+CALL :Stage chapter-14-gear
 
 REM Publish or perish
 cd book\book\wasm