Reserved names in FTL
The following names cannot be used for top-level variables without square-bracket syntax (as .vars["in"]), since they are keywords in FTL:
true: boolean value "true"false: boolean value "false"gt: comparison operator "greater than"gte: comparison operator "greater than or equivalent"lt: comparison operator "less than"lte: comparison operator "less than or equivalent"as: used by a few directivesin: used by a few directivesusing: used by a few directives