From 5ff282c9807a980f372bdec9c0738ac78f3253a8 Mon Sep 17 00:00:00 2001
From: Dima Zen <zen.dev@yandex.com>
Date: Fri, 19 May 2017 21:03:56 +0300
Subject: [PATCH] GH-96 Add uniquing identifier for Mapping

---
 FastEasyMapping/Source/Mapping/FEMMapping.h | 3 +++
 FastEasyMapping/Source/Mapping/FEMMapping.m | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/FastEasyMapping/Source/Mapping/FEMMapping.h b/FastEasyMapping/Source/Mapping/FEMMapping.h
index 202ad47..cd8d544 100644
--- a/FastEasyMapping/Source/Mapping/FEMMapping.h
+++ b/FastEasyMapping/Source/Mapping/FEMMapping.h
@@ -87,6 +87,9 @@ NS_ASSUME_NONNULL_BEGIN
 /// CoreData entity name used during CoreData-targeted mapping. It can be nil for NSObject-targeted mappings.
 @property (nonatomic, copy, nullable) NSString *entityName;
 
+/// Opaque unique value that is used internally to combine different in-memory instances that describes same Class / Entity.
+@property (nonatomic, strong, readonly) NSNumber *uniquingIdentifier;
+
 /**
  @brief path to the Object's representation in the JSON. Same as `keyPath` property of the `FEMProperty` protocol. 
  
diff --git a/FastEasyMapping/Source/Mapping/FEMMapping.m b/FastEasyMapping/Source/Mapping/FEMMapping.m
index a7274ce..ce995d8 100644
--- a/FastEasyMapping/Source/Mapping/FEMMapping.m
+++ b/FastEasyMapping/Source/Mapping/FEMMapping.m
@@ -20,6 +20,7 @@ - (instancetype)initWithObjectClass:(Class)objectClass {
         _relationshipMap = [NSMutableDictionary new];
 
         _objectClass = objectClass;
+        _uniquingIdentifier = @((NSUInteger)objectClass);
     }
 
     return self;
@@ -41,6 +42,7 @@ - (instancetype)initWithEntityName:(NSString *)entityName {
         _relationshipMap = [NSMutableDictionary new];
 
         _entityName = [entityName copy];
+        _uniquingIdentifier = @(entityName.hash);
     }
 
     return self;