module Annot:sig..end
type |    | innermost :  | 
|    | outermost :  | 
typetag =[ `Start of string | `Stop ] * (Lexing.position * layer_info)
typefilter =[ `All | `Innermost | `Outermost ]
val parse : impl_file:string -> annot_file:string -> tag list
val guess_annot_file : string -> string option
val from_file : impl_file:string -> annot_file:string -> tag list option