Fix SO

Author: nblumhardt

src/Serilog.Expressions/Expressions/Ast/IndexerExpression.cs

@@ -10,5 +10,10 @@ public IndexerExpression(Expression receiver, Expression index)
             Receiver = receiver;
             Index = index;
         }
+
+        public override string ToString()
+        {
+            return $"{Receiver}[{Index}]";
+        }
     }
 }

src/Serilog.Expressions/Expressions/Compilation/Transformations/NodeReplacer.cs

@@ -74,5 +74,21 @@ protected override Expression Transform(IndexerWildcardExpression wx)
 
             return base.Transform(wx);
         }
+
+        protected override Expression Transform(IndexerExpression ix)
+        {
+            if (ix == _source)
+                return _dest;
+            
+            return base.Transform(ix);
+        }
+        
+        protected override Expression Transform(ArrayExpression ax)
+        {
+            if (ax == _source)
+                return _dest;
+            
+            return base.Transform(ax);
+        }
     }
 }