Fixed a raylib-d bug with DUB.

README.md

@@ -53,6 +53,7 @@ While DUB simplifies the setup process, Popka itself doesn't require DUB.
     ```
 
     Popka doesn't require raylib-d, but we include it as a dependency for its convenient raylib download script.
+    It is recommended to remove raylib-d from your dub.json file after the installation is complete.
 
 2. **Compile example**
 

source/popka/vendor/ray/raylibpp.d

@@ -7,6 +7,9 @@ module popka.vendor.ray.raylibpp;
 
 import popka.vendor.ray.raylib;
 
+enum isRaylibPackageAvailable = is(typeof((){import raylib;}));
+
+static if (!isRaylibPackageAvailable) {
     // Basic shapes drawing functions
     alias drawPixel = DrawPixel;
     alias drawPixel = DrawPixelV;
@@ -162,16 +165,6 @@ alias drawBillboard = DrawBillboardPro;
     alias drawMesh = DrawMesh;
     alias drawMeshInstanced = DrawMeshInstanced;
 
-version (WebAssembly) {
-    @nogc nothrow extern(C)
-    void emscripten_set_main_loop(void* ptr, int fps, int loop);
-    @nogc nothrow extern(C)
-    void emscripten_cancel_main_loop();
-}
-
-// We intentionally leave attributes out to provide maximum flexibility for any use case.
-// The given function should return a bool value.
-// A return value of true will exit the loop, while false will allow it to continue.
     void updateWindow(alias loopFunc)() {
         version(WebAssembly) {
             static void __loopFunc() {
@@ -207,3 +200,13 @@ mixin template addRayStart(alias startFunc) {
             }
         }
     }
+} else {
+    pragma(msg, "Helper functions are not available when raylib-d is a DUB dependecy. Remove raylib-d from your dub.json file.");
+}
+
+version (WebAssembly) {
+    @nogc nothrow extern(C)
+    void emscripten_set_main_loop(void* ptr, int fps, int loop);
+    @nogc nothrow extern(C)
+    void emscripten_cancel_main_loop();
+}

web/source/app.d

@@ -143,7 +143,7 @@ int main(string[] args) {
     auto mode = args.length > 1 ? args[1] : "";
     if (mode != "build" && mode != "run") {
         writeln("Error: `", mode, "` isn't a mode.\nAvailable modes: [build, run]");
-        return -1;
+        return 1;
     }
 
 	// Can pass extra flags to ldc if needed.