From 125c9e7d40f8780dc9d6e8ddb62cb9411320b0b5 Mon Sep 17 00:00:00 2001
From: Mergul <wismerchil@interia.eu>
Date: Mon, 1 Oct 2018 15:08:14 +0200
Subject: [PATCH] -support for 'length' parameter in EntitiesData (for
 convenience)

---
 source/ecs/manager.d | 23 +++++++++++++++++++----
 source/ecs/system.d  |  2 ++
 tests/tests.d        |  4 +++-
 3 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/source/ecs/manager.d b/source/ecs/manager.d
index 9dc7eff..11556cd 100644
--- a/source/ecs/manager.d
+++ b/source/ecs/manager.d
@@ -78,11 +78,17 @@ class EntityManager
             {
                 static if (isFunction!(__traits(getMember, Sys.EntitiesData, member)))
                     static assert(0, "EntitiesData can't have any function!");
+                else static if(member == "length")
+                {
+                    static assert(isIntegral!(typeof(__traits(getMember,Sys.EntitiesData, member))),"EntitiesData 'length' member must be integral type.");
+                    static assert(typeof(__traits(getMember,Sys.EntitiesData, member)).sizeof > 1,"EntitiesData 'length' member can't be byte or ubyte.");
+                }
                 else static if (!(isArray!(typeof(__traits(getMember,
                         Sys.EntitiesData, member)))))
                     static assert(0, "EntitiesData members should be arrays of elements!");
                 else static if (is(typeof(__traits(getMember, Sys.EntitiesData,
-                        member)) == Entity[]))
+                        member)) == Entity[]) || is(typeof(__traits(getMember,
+                        Sys.EntitiesData, member)) == const(Entity)[]))
                 {
                     //ret ~= "const string entities_name = \"" ~ member ~ "\";";
                 }
@@ -124,6 +130,10 @@ class EntityManager
                         Sys.EntitiesData, member)) == const(Entity)[]))
                 {
                     //ret ~= "const string entities_name = \"" ~ member ~ "\";";
+                }
+                else static if(member == "length")
+                {
+
                 }
                 else
                 {
@@ -198,6 +208,11 @@ class EntityManager
                         ret ~= "input_data." ~ member
                             ~ " = (cast(Entity*) block.dataBegin())[0 .. block.entities_count];";
                     }
+                    else if(member == "length")
+                    {
+                        ret ~= "input_data." ~ member
+                            ~ " = block.entities_count;";
+                    }
                     else
                     {
                         {
@@ -306,8 +321,8 @@ class EntityManager
         }
         else
         {
-            string name = Mallocator.instance.makeArray(Sys.stringof);
-            systems_map.add(name, cast(ushort) systems.length);
+            system.name = Mallocator.instance.makeArray(Sys.stringof);
+            systems_map.add(system.name, cast(ushort) systems.length);
 
             systems.add(system);
 
@@ -1240,7 +1255,7 @@ class EntityManager
     Vector!ubyte change_entities_list;
 
     HashMap!(ushort[], EntityInfo*) entities_infos;
-    HashMap!(string, ushort) systems_map;
+    HashMap!(const (char)[], ushort) systems_map;
     HashMap!(string, ushort) components_map;
     HashMap!(string, ushort) events_map;
     Vector!System systems;
diff --git a/source/ecs/system.d b/source/ecs/system.d
index 1276d86..b202d94 100644
--- a/source/ecs/system.d
+++ b/source/ecs/system.d
@@ -38,6 +38,8 @@ package:
     ///pointer to system implementation
     void* m_system_pointer;
 
+    const (char)[] name;
+
     ushort[] m_components;
     ushort[] m_absen_components;
     ushort[] m_optional_components;
diff --git a/tests/tests.d b/tests/tests.d
index 6947b29..8cdc402 100644
--- a/tests/tests.d
+++ b/tests/tests.d
@@ -127,6 +127,7 @@ int main()
 
 		static struct EntitiesData
 		{
+			size_t length;
 			TestComp[] test;
 			TestComp2[] test2;
 			@optional TestComp3[] test3;
@@ -147,7 +148,7 @@ int main()
 
 		void update(ref EntitiesData data)
 		{
-			foreach(i;0..data.test.length)
+			foreach(i;0..data.length)
 			{
 				data.test[i].a += 1000;
 				data.test[i].b += 2000;
@@ -193,6 +194,7 @@ int main()
 
 		static struct EntitiesData
 		{
+			short length;
 			Entity[] entity;
 			TestComp3[] test;
 		}