diff --git a/src/Parser/XnParser.cs b/src/Parser/XnParser.cs
index 1e7c54e..0a6e086 100644
--- a/src/Parser/XnParser.cs
+++ b/src/Parser/XnParser.cs
@@ -12,6 +12,7 @@ using Rule = XNeedle.Transformation.Rule;
 using System.Data;
 using System.ComponentModel.DataAnnotations;
 using System.Text;
+using System.Security.AccessControl;
 
 namespace XNeedle.Parser
 {
@@ -126,7 +127,18 @@ namespace XNeedle.Parser
 
         static Parser<Expression> Term(Context ctx)
         {
-            return Parse.ChainOperator(Multiply.Or(Divide).Or(Modulo).Or(BitwiseXor).Or(BitwiseAnd).Or(BitwiseOr), InnerTerm(ctx), Expression.MakeBinary);
+            return Parse.ChainOperator(Multiply.Or(Divide), InnerTerm(ctx), Expression.MakeBinary);
+        }
+
+        static Parser<Expression> IntegerTerm(Context ctx)
+        {
+            // Integer operations can't deal with doubles, so we need to make unary casts to integer and back
+            return Parse.ChainOperator(Multiply.Or(Divide).Or(Modulo).Or(BitwiseXor).Or(BitwiseAnd).Or(BitwiseOr), 
+                    InnerTerm(ctx), (bt,left,right)=>Expression.MakeUnary(
+                        ExpressionType.Convert, Expression.MakeBinary(bt, 
+                            Expression.MakeUnary(ExpressionType.Convert, left, typeof(long)), 
+                            Expression.MakeUnary(ExpressionType.Convert, right, typeof(long))), 
+                    typeof(double)));
         }
 
         static Parser<Expression> ConcatExpr(Context ctx)
@@ -141,7 +153,7 @@ namespace XNeedle.Parser
 
         static Parser<Expression> ArithExpr(Context ctx)
         {
-            return Parse.ChainOperator(Add.Or(Subtract), Term(ctx), Expression.MakeBinary);
+            return Parse.ChainOperator(Add.Or(Subtract), IntegerTerm(ctx).Or(Term(ctx)), Expression.MakeBinary);
         }
 
         static Parser<Expression> Expr(Context ctx)