Added error fallback methods

.gitignore

@@ -107,3 +107,5 @@ Generated_Code #added for RIA/Silverlight projects
 _UpgradeReport_Files/
 Backup*/
 UpgradeLog*.XML
+
+\.idea/

Chain/Chain.cs

@@ -1,18 +1,24 @@
-
-using System;
+using System;
 
 namespace Chain
 {
     public abstract class Chain
     {
         public static OngoingChaining<T> Do<T>(Func<T> startFunction) where T : class
         {
-            return new OngoingChaining<T>(startFunction());
+            try
+            {
+                return new OngoingChaining<T>(startFunction());
+            }
+            catch
+            {
+                return new OngoingChaining<T>(null);
+            }
         }
 
         public static OngoingChaining<T> Do<T>(T startObject) where T : class
         {
             return new OngoingChaining<T>(startObject);
         }
     }
-}
+}

Chain/OngoingChaining.cs

@@ -4,16 +4,44 @@ namespace Chain
 {
     public class OngoingChaining<T> where T : class
     {
-        private  T _currentResult;
+        private T _currentResult;
+        private Action<Exception> _errorFallback;
+        private Action<Exception> _globalErrorFallback;
 
         internal OngoingChaining(T currentResult)
         {
             _currentResult = currentResult;
         }
 
+        public OngoingChaining<T> WithErrorFallback(Action<Exception> onError)
+        {
+            _errorFallback = onError;
+            return this;
+        }
+
+        public OngoingChaining<T> WithGlobalErrorFallback(Action<Exception> onError)
+        {
+            _globalErrorFallback = onError;
+            return this;
+        }
+
         public OngoingChaining<TNext> Then<TNext>(Func<T, TNext> nextFunction) where TNext : class
         {
-            return _currentResult != null ? new OngoingChaining<TNext>(nextFunction(_currentResult)) : new OngoingChaining<TNext>(null);
+            try
+            {
+                var result = _currentResult != null
+                    ? new OngoingChaining<TNext>(nextFunction(_currentResult))
+                    : new OngoingChaining<TNext>(null);
+
+                _errorFallback = null;
+                return result;
+            }
+            catch (Exception ex)
+            {
+                _errorFallback?.Invoke(ex);
+                _globalErrorFallback?.Invoke(ex);
+                return null;
+            }
         }
 
         public OngoingChaining<T> OrElse(T fallback)