It's left to right.

Given we don't have parentheses, there's no way to override operator precedence if AND always took precedence over OR. So, if we were to change this so AND took precedence over OR, then we'd have to add parens, too. That's doable, but it'd take me a day or so to figure out how to rewrite things to support that.

For this pass, I wrote the minimal feature set figuring if it proved problematic we could extend it.