% is a proper modulus operator, not reminder. #fixes 842, #fixes 843

src/main/java/carpet/script/language/Operators.java

@@ -80,7 +80,7 @@ public class Operators {
         expression.addFunctionalEquivalence("/", "quotient");
 
         expression.addBinaryOperator("%", precedence.get("multiplication*/%"), true, (v1, v2) ->
-                new NumericValue(NumericValue.asNumber(v1).getDouble() % NumericValue.asNumber(v2).getDouble()));
+                NumericValue.asNumber(v1).mod(NumericValue.asNumber(v2)));
         expression.addBinaryOperator("^", precedence.get("exponent^"), false, (v1, v2) ->
                 new NumericValue(java.lang.Math.pow(NumericValue.asNumber(v1).getDouble(), NumericValue.asNumber(v2).getDouble())));
 

src/main/java/carpet/script/value/NumericValue.java

@@ -313,4 +313,14 @@ public class NumericValue extends Value
     {
         return longValue!= null ||  getDouble() == (double)getLong();
     }
+
+    public Value mod(NumericValue n2)
+    {
+        if (this.longValue != null && n2.longValue != null)
+            return new NumericValue(Math.floorMod(longValue, n2.longValue));
+        double x = value;
+        double y = n2.value;
+        if (y == 0) throw new ArithmeticException("Division by zero");
+        return new NumericValue( x - Math.floor(x / y) * y);
+    }
 }