Properly link flecs library

engine/libs/flecs/examples/cpp/relationships/symmetric_relations/include/symmetric_relations.h

@@ -0,0 +1,16 @@
+#ifndef SYMMETRIC_RELATIONS_H
+#define SYMMETRIC_RELATIONS_H
+
+/* This generated file contains includes for project dependencies */
+#include "symmetric_relations/bake_config.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+

engine/libs/flecs/examples/cpp/relationships/symmetric_relations/include/symmetric_relations/bake_config.h

@@ -0,0 +1,24 @@
+/*
+                                   )
+                                  (.)
+                                  .|.
+                                  | |
+                              _.--| |--._
+                           .-';  ;`-'& ; `&.
+                          \   &  ;    &   &_/
+                           |"""---...---"""|
+                           \ | | | | | | | /
+                            `---.|.|.|.---'
+
+ * This file is generated by bake.lang.c for your convenience. Headers of
+ * dependencies will automatically show up in this file. Include bake_config.h
+ * in your main project file. Do not edit! */
+
+#ifndef SYMMETRIC_RELATIONS_BAKE_CONFIG_H
+#define SYMMETRIC_RELATIONS_BAKE_CONFIG_H
+
+/* Headers of public dependencies */
+#include <flecs.h>
+
+#endif
+

engine/libs/flecs/examples/cpp/relationships/symmetric_relations/project.json

@@ -0,0 +1,11 @@
+{
+    "id": "symmetric_relations",
+    "type": "application",
+    "value": {
+        "use": [
+            "flecs"
+        ],
+        "public": false,
+        "language": "c++"
+    }
+}

engine/libs/flecs/examples/cpp/relationships/symmetric_relations/src/main.cpp

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+#include <symmetric_relations.h>
+#include <iostream>
+
+// Type for TradesWith relationship
+struct TradesWith { };
+
+int main(int, char*[]) {
+    flecs::world ecs;
+
+    // Register TradesWith as symmetric relationship. Symmetric relationships
+    // go both ways, adding (R, B) to A will also add (R, A) to B.
+    ecs.component<TradesWith>()
+        .add(flecs::Symmetric);
+
+    // Create two players
+    flecs::entity player_1 = ecs.entity();
+    flecs::entity player_2 = ecs.entity();
+
+    // Add (TradesWith, player_2) to player_1. This also adds 
+    // (TradesWith, player_1) to player_2.
+    player_1.add<TradesWith>(player_2);
+
+    // Log platoon of unit
+    std::cout << "Player 1 trades with Player 2: " << 
+        (player_1.has<TradesWith>(player_2) ? "true" : "false") << "\n";
+    std::cout << "Player 2 trades with Player 1: " << 
+        (player_2.has<TradesWith>(player_1) ? "true" : "false") << "\n";
+
+    // Output:
+    //  Player 1 trades with Player 2: true
+    //  Player 2 trades with Player 1: true
+}