type atom =
  | AInt of int
  | ABool of bool
  | AString of string
  | AUnit
  | AVar of Ident.t

type expr = {
  a : desc;
  aty : Types.t;
  aspan : Location.span;
}

and desc =
  | AAtom of atom
  | ALet of Ident.t * expr * expr
  | ABinop of Syntax.binop * atom * atom
  | AIf of atom * expr * expr
  | ATuple of atom list
  | ARecord of string * (string * atom) list
  | AField of atom * string
  | AApp of Ident.t * atom
  | ALambda of Ident.t * expr
  | AFilter of atom * Ident.t * expr
  | AMap of atom * Ident.t * expr
  | ASum of atom
  | ACount of atom

type program = {
  ap_input : Ident.t;
  ap_input_element : Types.t;
  ap_query : Ident.t;
  ap_query_body : expr;
  ap_helpers : (Ident.t * Types.scheme * expr) list;
}

val reset : unit -> unit
val program : Typed.program -> program
val to_string : expr -> string
val atom_to_string : atom -> string
val program_to_string : program -> string
val validate : Ident.t list -> expr -> unit