Plus vs. Minus Signs in Roll Query Inputs

Having an annoying issue that I'm sure someone else must be experiencing and/or have a solution for. I'm using a roll query in a custom character sheet roll button that outputs the roll info to a roll template, like this: <button type='roll' class='combatbutton' value='@{whispertoggle} &{template:custom} {{title=@{banner_surprise} **@{character_title} @{selected|token_name}**}} {{subtitle=Surprise Check}} {{Surprise=[[1d6cs0cf0+@{class_surprise_bonus}[class]-@{has_helm}[helm]+@{mod_surprise}[mod1]+?{Modifier|0}[mod2]]]}}' name='roll_surprise'> Surprise</button> At the end of the {{Surprise}} [[roll]] clause is a roll query that prompts the user for an additional 'Modifier', if any. If the number entered by the user is signed negative, the button roll works as expected. However, if the user enters a plus sign (which is natural for a user to do), it breaks the roll. The output displays as '++' which I suspect is breaking the parser. While the work-around is simply enough ("don't enter plus signs") but people forget and the roll calculations break at the worst times. Any ways to address this?

Wrap the query in parenthesis, that will fix the problem. 

You are correct that ++ is breaking ther parser.

Gauss said: Wrap the query in parenthesis, that will fix the problem.  Saved again by GiGs! That worked.  WHY?

It was gauss who pointed it out :) But the parser breaks on two signs, like ++ or --. However, if you put something in parenthesis it is evaluated as a number. So when someone enters the + sign, it gets treated as a sign of the number, not as a separate addition operator. You sometimes have to do this in complex expressions even when they don't include queries.

Thanks!