broadcast project (#918)

* broadcast project

* revert chaanges

libs/broadcast/broadcast.ts

@@ -0,0 +1,66 @@
+/**
+ * Message broadcasting
+ */
+//% weight=70
+//% color="#58AB41"
+namespace broadcast {
+    const broadcastEventId = control.allocateNotifyEvent();
+    const broadcastDoneEventId = control.allocateNotifyEvent();
+
+    function normalizeId(id: number) {
+        // upper ids are reserved for answer
+        return ((id + 1) | 0) & 0xffff;
+    }
+
+    /**
+     * An enum shim
+     */
+    //% shim=ENUM_GET
+    //% blockId=msg_enum_shim
+    //% block="$arg"
+    //% enumName="Messages"
+    //% enumMemberName="message"
+    //% enumPromptHint="e.g. Move, Turn, ..."
+    //% enumInitialMembers="message1"
+    //% blockHidden=1
+    //% enumIsHash=1
+    export function __messageShim(arg: number) {
+        // This function should do nothing, but must take in a single
+        // argument of type number and return a number value.
+        return arg;
+    }
+
+    /**
+     * Register code to run when a message is received
+     */
+    //% block="on %id=msg_enum_shim|received"
+    //% blockId=broadcastonreceived draggableParameters
+    export function onMessageReceived(message: number, body: () => void) {
+        const messageid = normalizeId(message);
+        control.onEvent(broadcastEventId, messageid, function () {
+            body();
+            control.raiseEvent(broadcastDoneEventId, messageid);
+        })
+    }
+
+    /**
+     * Sends a message to activate code
+     */
+    //% block="send %id=msg_enum_shim"
+    //% blockId=broadcastsend draggableParameters
+    export function sendMessage(message: number) {
+        const messageid = normalizeId(message);
+        control.raiseEvent(broadcastEventId, messageid);
+    }
+
+    /**
+     * Sends a message and pauses until the handler to finishes.
+     */
+    //% block="send %id=msg_enum_shim| and pause"
+    //% blockId=broadcastsendpause
+    export function sendMessageAndPause(message: number) {
+        const messageid = normalizeId(message);
+        control.raiseEvent(broadcastEventId, messageid);
+        control.waitForEvent(broadcastDoneEventId, messageid);
+    }
+}

libs/broadcast/pxt.json

@@ -0,0 +1,11 @@
+{
+    "name": "broadcast",
+    "description": "Broadcasting messages - beta",
+    "files": [
+        "broadcast.ts"
+    ],
+    "public": true,
+    "dependencies": {
+            "core": "file:../core"
+    }
+}