upd

Author: mattqual

TODO

@@ -78,6 +78,8 @@
   - [ ] `T!`
 - [ ] Statements
   - [ ] For `for each`: `Iterator` and `Iterable` are iterable
+  - [ ] `use effect`
+    - [ ] `cleanup {}`
   - [ ] `switch`
     - [ ] No fallthroughs (demonstrate too).
   - [ ] `switch type`

src/_BASE/statements/use-effect.md

@@ -0,0 +1,20 @@
+# Use effect
+
+The `use effect` statement consists of implementation-defined behavior, however it is usually used to detect state or parameter changes or implement mount and unmount routines for a component.
+
+```
+use effect [] {
+    //
+}
+use effect [dep1, ...depN] {
+    //
+}
+use effect * {
+    //
+}
+use effect * {
+    cleanup {
+        //
+    }
+}
+```

src/lexical-conventions.md

@@ -359,9 +359,12 @@ type
 Embed
 final
 
+effect
 native
 static
 
+cleanup
+
 abstract
 override
 

src/overview/relation/mxml.md

@@ -21,4 +21,25 @@ package com.business.components {
 
 In MXML, event handlers were expressed as `e="statements"`. In ShockScript, they are expressed as `e&={statements}` (note the ampersand **\&**) as a shorthand to `e={function(event){statements}}`.
 
-> **Note**: Although not demanded as such, as opposed to React.js + DOM, event handlers are conventionally expressed without a `on` prefix, such as `click&={trace("clicked!")}` rather than React.js `onClick={e=>{console.log("clicked!")}}`. Event parameters are conventionally given the `@eventparam` tag in the ShockDoc comments. Classes continue using the `Event` meta-data, though without needing the `@eventType` tag.
+> **Note**: Although not demanded as such, as opposed to React.js + DOM, event handlers are conventionally expressed without a `on` prefix, such as `click&={trace("clicked!")}` rather than React.js `onClick={e=>{console.log("clicked!")}}`. Event parameters are conventionally given the `@eventparam` tag in the ShockDoc comments. Classes continue using the `Event` meta-data, though without needing the `@eventType` tag.
+
+## Use effect
+
+The `use effect` statement may be used to detect state and parameter changes as well as the component mount and unmount phases.
+
+```
+use effect [] {
+    //
+}
+use effect [dep1, ...depN] {
+    //
+}
+use effect * {
+    //
+}
+use effect * {
+    cleanup {
+        //
+    }
+}
+```

src/overview/relation/reactjs.md

@@ -102,14 +102,34 @@ package com.business.components {
         [Reference]
         var button:Button? = null;
 
-        // did mount
-        Fuse::useEffect(function() {
+        use effect [] {
             trace(button!);
-        }, []);
+        }
 
         return (
             <j:Button reference={button}>click me</j:Button>
         );
     }
 }
+```
+
+## Effects
+
+The popular "use effect" hook is abbreviated as an `use effect` statement.
+
+```
+use effect [] {
+    //
+}
+use effect [dep1, ...depN] {
+    //
+}
+use effect * {
+    //
+}
+use effect * {
+    cleanup {
+        //
+    }
+}
 ```