these are public functions, not for internal use

src/game.rs

@@ -210,14 +210,14 @@ impl ToString for Game {
 }
 
 impl Game {
-    fn tile_ids(&self) -> Vec<u64> {
+    pub fn tile_ids(&self) -> Vec<u64> {
         self.tiles.iter().map(|tile| {tile.id}).collect()
     }
 
     /// first available tile ID.
     /// e.g. if current tile IDs are [0, 2, 3] the result will be `1`
     ///      if current tile IDs are [0, 1, 2] the result will be `3`
-    fn new_tile_id(&self) -> u64 {
+    pub fn new_tile_id(&self) -> u64 {
         let mut new_id = 0;
 
         let mut ids = self.tile_ids();
@@ -234,7 +234,7 @@ impl Game {
         new_id + 1
     }
     /// adds a tile safely and returns the new tile ID
-    fn add_tile(&mut self, mut tile: Tile) -> u64 {
+    pub fn add_tile(&mut self, mut tile: Tile) -> u64 {
         let new_id = self.new_tile_id();
         tile.id = new_id;
         self.tiles.push(tile);