Add isDeleted (#2445)

docs/reference/game/is-deleted.md

@@ -0,0 +1,33 @@
+# Is Deleted
+
+Find out if the sprite is deleted from the game engine or not.
+
+```sig
+game.createSprite(0,0).isDeleted()
+```
+
+## Returns
+
+* a [boolean](/types/boolean) value that is `true` if the sprite is deleted from the game engine or `false` if not.
+
+## Example
+
+This game has 5 sprites initially. After 1 second, the third sprite is deleted and all remaining sprites are moved by 1.
+
+```blocks
+let sprites: game.LedSprite[] = []
+for (let i = 0; i <= 4; i++) {
+    sprites.push(game.createSprite(0, i))
+}
+basic.pause(1000)
+sprites[2].delete()
+for (let sprite of sprites) {
+    if (!(sprite.isDeleted())) {
+        sprite.move(1)
+    }
+}
+```
+
+## See also
+
+[delete sprite](/reference/game/delete)

libs/core/_locales/core-jsdoc-strings.json

@@ -281,6 +281,7 @@
   "game.LedSprite.goTo|param|x": "TODO",
   "game.LedSprite.goTo|param|y": "TODO",
   "game.LedSprite.ifOnEdgeBounce": "If touching the edge of the stage and facing towards it, then turn away.",
+  "game.LedSprite.isDeleted": "Reports whether the sprite has been deleted from the game engine.",
   "game.LedSprite.isTouching": "Reports true if sprite has the same position as specified sprite",
   "game.LedSprite.isTouchingEdge": "Reports true if sprite is touching an edge",
   "game.LedSprite.isTouching|param|other": "the other sprite to check overlap or touch",

libs/core/_locales/core-strings.json

@@ -266,6 +266,7 @@
   "game.LedSprite.delete|block": "delete %this(sprite)",
   "game.LedSprite.get|block": "%sprite|%property",
   "game.LedSprite.ifOnEdgeBounce|block": "%sprite|if on edge, bounce",
+  "game.LedSprite.isDeleted|block": "is %sprite|deleted",
   "game.LedSprite.isTouchingEdge|block": "is %sprite|touching edge",
   "game.LedSprite.isTouching|block": "is %sprite|touching %other",
   "game.LedSprite.move|block": "%sprite|move by %leds",

libs/core/game.ts

@@ -695,7 +695,7 @@ namespace game {
          * Deletes the sprite from the game engine. The sprite will no longer appear on the screen or interact with other sprites.
          * @param this sprite to delete
          */
-        //% weight=59 help=game/delete
+        //% weight=59 blockGap=8 help=game/delete
         //% blockId="game_delete_sprite" block="delete %this(sprite)"
         public delete(): void {
             this._enabled = false;
@@ -703,6 +703,15 @@ namespace game {
                 plot();
         }
 
+        /**
+         * Reports whether the sprite has been deleted from the game engine.
+         */
+        //% weight=58 help=game/is-deleted
+        //% blockId="game_sprite_is_deleted" block="is %sprite|deleted"
+        public isDeleted(): boolean {
+            return !this._enabled;
+        }
+
         /**
          * Sets the blink duration interval in millisecond.
          * @param sprite TODO