This module provide a way to transform a type into strings, in such a way that the strings can be used for type search.

The type of a search database.

db_names is for text-based part of the query and db_types for the type-based part.

db_types has Entry.t array Int_map.t (Occ.t) as a payload because we want the query blabla : int -> int -> _ to return only entries that take at least two ints as arguments, an entry of type int -> string is invalid. The Int_map.t maps a number of occurences to a set of entries. See Occ. db_types still is a suffix tree, so you can search in it only for text. The way we transform types into searchable text is in Type_polarity.