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open Types
(* Print x prefixed with tag and return x unchanged. *)
let print (f : 'a -> string) (tag : string) (x : 'a) : 'a =
Printf.printf "%s: %s\n" tag (f x);
x
let rec ast (tree : Types.value) : string =
match tree with
| ValueLiteral (LiteralBool x) ->
Printf.sprintf "ValueLiteral (LiteralBool %s)" (string_of_bool x)
| ValueLiteral (LiteralInt x) ->
Printf.sprintf "ValueLiteral (LiteralInt %s)" (string_of_int x)
| ValueVariable x ->
Printf.sprintf "ValueVariable %s" x
| ValueFunction (x, body) ->
Printf.sprintf "ValueFunction (%s, %s)" x (ast body)
| ValueApplication (f, x) ->
Printf.sprintf "ValueApplication (%s, %s)" (ast f) (ast x)
| ValueVarApplication (f, x) ->
Printf.sprintf "ValueVarApplication (%s, %s)" f (ast x)
| ValueBinder (k, v, x) ->
Printf.sprintf "ValueBinder (%s, %s, %s)" k (ast v) (ast x)
let rec value (x : value) : string =
match x with
| ValueLiteral (LiteralInt x) ->
Printf.sprintf "Int %d" x
| ValueLiteral (LiteralBool x) ->
Printf.sprintf "Bool %b" x
| ValueVariable x ->
Printf.sprintf "Var %s" x
| ValueFunction (name, x) ->
Printf.sprintf "Fn %s %s" name (value x)
| ValueApplication (f, x) ->
Printf.sprintf "App %s %s" (value f) (value x)
| ValueVarApplication (name, x) ->
Printf.sprintf "App %s %s" name (value x)
| ValueBinder (name, x, body) ->
Printf.sprintf "Bind %s %s %s" name (value x) (value body)
let rec type' (t : _type) : string =
match t with
| TypeInt -> "Integer"
| TypeBool -> "Boolean"
| TypeVariable k -> Printf.sprintf "%s" k
| TypeArrow (a, b) -> Printf.sprintf "%s -> %s" (type' a) (type' b)
let quantified_type (q : quantified_type) : string =
let QuantifiedType (vars, t) = q in
if List.length vars == 0 then
Printf.sprintf "%s" (type' t)
else
Printf.sprintf "forall %s. %s" (String.concat "," vars) (type' t)
let substitution (s : substitution) : string =
FromString.fold (fun k v acc -> Printf.sprintf "%s\"%s\" |-> %s;" acc k (type' v)) s ""
|> Printf.sprintf "{ %s }"
let env (s : env) : string =
FromString.fold (fun k v acc -> Printf.sprintf "%s\"%s\" |-> %s;" acc k (quantified_type v)) s ""
|> Printf.sprintf "{ %s }"
let inference (Inference (s, t)) =
Printf.sprintf "type: %s; sub: %s" (type' t) (substitution s)
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