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program.ml
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program.ml
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open Core
open Parser
open Utils
open Type
type program =
| Index of int
| Abstraction of program
| Apply of program*program
| Primitive of tp * string * (unit ref)
| Invented of tp * program
let is_index = function
|Index(_) -> true
|_ -> false
let get_index_value = function
| Index(n) -> n
|_ -> assert false
let is_primitive = function
|Primitive(_,_,_) -> true
|Invented(_,_) -> true
|_ -> false
let is_base_primitive = function
|Primitive(_,_,_) -> true
|_ -> false
let is_abstraction = function
| Abstraction(_) -> true
| _ -> false
let rec recursively_get_abstraction_body = function
| Abstraction(b) -> recursively_get_abstraction_body b
| e -> e
let rec wrap_with_abstractions n e =
if n=0 then e else wrap_with_abstractions (n-1) (Abstraction(e))
let program_children = function
| Abstraction(b) -> [b]
| Apply(m,n) -> [m;n]
| _ -> []
let rec application_function = function
| Apply(f,x) -> application_function f
| e -> e
let rec application_parse = function
| Apply(f,x) ->
let (f,arguments) = application_parse f in
(f,arguments @ [x])
| f -> (f,[])
let rec program_size = function
| Apply(f,x) -> program_size f + program_size x
| Abstraction(b) -> program_size b
| Index(_) | Invented(_,_) | Primitive(_,_,_) -> 1
let rec program_subexpressions p =
p::(List.map (program_children p) program_subexpressions |> List.concat)
let rec show_program (is_function : bool) = function
| Index(j) -> "$" ^ string_of_int j
| Abstraction(body) ->
"(lambda "^show_program false body^")"
| Apply(p,q) ->
if is_function then
show_program true p^" "^show_program false q
else
"("^show_program true p^" "^show_program false q^")"
| Primitive(_,n,_) -> n
| Invented(_,i) -> "#"^show_program false i
let string_of_program = show_program false
let primitive_name = function | Primitive(_,n,_) -> n
| e -> raise (Failure ("primitive_name: "^string_of_program e^"not a primitive"))
let rec program_equal p1 p2 = match (p1,p2) with
| (Primitive(_,n1,_),Primitive(_,n2,_)) -> n1 = n2
| (Abstraction(a),Abstraction(b)) -> program_equal a b
| (Invented(_,a),Invented(_,b)) -> program_equal a b
| (Index(a),Index(b)) -> a = b
| (Apply(a,b), Apply(x,y)) -> program_equal a x && program_equal b y
| _ -> false
let rec compare_program p1 p2 = match (p1,p2) with
(* Negative if p1 is smaller; 0 if they are equal; positive if p1 is bigger *)
(* intuitively calculates (p1 - p2) *)
| (Index(i),Index(j)) -> i - j
| (Index(_),_) -> -1
| (Abstraction(b1),Abstraction(b2)) -> compare_program b1 b2
| (Abstraction(_),_) -> -1
| (Apply(p,q),Apply(m,n)) ->
let c = compare_program p m in
if c = 0 then compare_program q n else c
| (Apply(_,_),_) -> -1
| (Primitive(_,n1,_),Primitive(_,n2,_)) -> String.compare n1 n2
| (Primitive(_,_,_),_) -> -1
| (Invented(_,b1),Invented(_,b2)) -> compare_program b1 b2
| (Invented(_,_),_) -> -1
exception UnboundVariable;;
let rec infer_program_type context environment p : tContext*tp = match p with
| Index(j) ->
(match List.nth environment j with
| None -> raise UnboundVariable
| Some(t) -> applyContext context t)
| Primitive(t,_,_) -> instantiate_type context t
| Invented(t,_) -> instantiate_type context t
| Abstraction(b) ->
let (xt,context) = makeTID context in
let (context,rt) = infer_program_type context (xt::environment) b in
applyContext context (xt @> rt)
| Apply(f,x) ->
let (rt,context) = makeTID context in
let (context, xt) = infer_program_type context environment x in
let (context, ft) = infer_program_type context environment f in
let context = unify context ft (xt @> rt) in
applyContext context rt
let closed_inference = snd % infer_program_type empty_context [];;
let make_invention i =
Invented(closed_inference i |> canonical_type, i)
(* let rec bidirectional_type_inference (environment : tp list) (request : tp) (p : program) : ((tp list)*tp) option = *)
(* match p with *)
(* | Index(j) -> *)
(* (match List.nth environment j with *)
(* | None -> raise UnboundVariable *)
(* | Some(t) -> *)
(* try *)
(* let k = unify empty_context t request in *)
(* Some((environment |> List.map ~f:(applyContext k), *)
(* applyContext k request)) *)
(* with UnificationFailure -> None *)
(* ) *)
(* | Primitive(t,_,_) | Invented(t,_) -> begin *)
(* let offset = *)
(* (request::environment) |> List.map ~f:next_type_variable |> List.reduce_exn l ~f:max *)
(* in *)
(* let t = add_constant_to_type_variables offset t in *)
(* try *)
(* let k = unify empty_context t request in *)
(* Some((environment |> List.map ~f:(applyContext k), *)
(* applyContext k request)) *)
(* with UnificationFailure -> None *)
(* end *)
(* | Abstraction(b) -> *)
(* let offset = *)
(* (request::environment) |> List.map ~f:next_type_variable |> List.reduce_exn l ~f:max *)
(* in *)
(* let environment' = TID(offset) :: environment in *)
(* match bidirectional_type_inference environment' *)
(* instantiate_type context t *)
exception UnknownPrimitive of string
let every_primitive : (program String.Table.t) = String.Table.create();;
let lookup_primitive n =
try
Hashtbl.find_exn every_primitive n
with _ -> raise (UnknownPrimitive n)
let [@warning "-20"] rec evaluate (environment: 'b list) (p:program) : 'a =
match p with
| Apply(Apply(Apply(Primitive(_,"if",_),branch),yes),no) ->
if magical (evaluate environment branch) then evaluate environment yes else evaluate environment no
| Abstraction(b) -> magical @@ fun argument -> evaluate (argument::environment) b
| Index(j) -> magical @@ List.nth_exn environment j
| Apply(f,x) -> (magical @@ evaluate environment f) (magical @@ evaluate environment x)
| Primitive(_,_,v) -> magical (!v)
| Invented(_,i) -> evaluate [] i
let rec analyze_evaluation (p:program) : 'b list -> 'a =
match p with
| Apply(Apply(Apply(Primitive(_,"if",_),branch),yes),no) ->
let branch = analyze_evaluation branch
and yes = analyze_evaluation yes
and no = analyze_evaluation no
in
fun environment ->
if magical (branch environment) then yes environment else no environment
| Abstraction(b) ->
let body = analyze_evaluation b in
fun environment -> magical (fun x -> body (x::environment))
| Index(j) ->
fun environment -> List.nth_exn environment j |> magical
| Apply(f,x) ->
let analyzed_function = analyze_evaluation f
and analyzed_argument = analyze_evaluation x
in
fun environment -> magical ((analyzed_function environment) (magical (analyzed_argument environment)))
| Primitive(_,_,v) ->
fun _ -> magical (!v)
| Invented(_,i) ->
let analyzed_body = analyze_evaluation i in
fun _ -> analyzed_body []
let run_with_arguments (p : program) (arguments : 'a list) =
let rec loop l xs =
match xs with
| [] -> magical l
| x :: xs -> loop (magical (l x)) xs
in loop (evaluate [] p) arguments
let run_analyzed_with_arguments (p : 'b list -> 'c) (arguments : 'a list) =
let rec loop l xs =
match xs with
| [] -> magical l
| x :: xs -> loop (magical (l x)) xs
in loop (p []) arguments
let [@warning "-20"] rec lazy_evaluate (environment: ('b Lazy.t) list) (p:program) : 'a Lazy.t =
(* invariant: always return thunks *)
match p with
(* Notice that we do not need to special case conditionals. In lazy
evaluation conditionals are function just like any other. *)
| Abstraction(b) -> lazy (magical @@ fun argument -> Lazy.force (lazy_evaluate (argument::environment) b))
| Index(j) -> magical @@ List.nth_exn environment j
| Apply(f,x) ->
lazy ((Lazy.force @@ magical @@ lazy_evaluate environment f) (magical @@ lazy_evaluate environment x))
| Primitive(_,_,v) -> lazy (magical (!v))
| Invented(_,i) -> lazy_evaluate [] i
let [@warning "-20"] rec analyze_lazy_evaluation (p:program) : (('b Lazy.t) list) -> 'a Lazy.t =
match p with
(* Notice that we do not need to special case conditionals. In lazy
evaluation conditionals are function just like any other. *)
| Abstraction(b) ->
let body = analyze_lazy_evaluation b in
fun environment ->
lazy (magical @@ fun argument -> Lazy.force (body (argument::environment)))
| Index(j) ->
fun environment -> magical @@ List.nth_exn environment j
| Apply(f,x) ->
let analyzed_function = analyze_lazy_evaluation f
and analyzed_argument = analyze_lazy_evaluation x
in
fun environment ->
lazy ((Lazy.force @@ magical @@ analyzed_function environment) (magical @@ analyzed_argument environment))
| Primitive(_,_,v) -> fun _ -> lazy (magical (!v))
| Invented(_,i) ->
let analyzed_body = analyze_lazy_evaluation i in
fun _ -> analyzed_body []
let [@warning "-20"] run_lazy_analyzed_with_arguments p arguments =
let rec go l xs =
match xs with
| [] -> l |> magical
| x :: xs -> go (lazy x |> magical l) xs
in go (p [] |> Lazy.force) arguments
let rec remove_abstractions (n : int) (q : program) : program =
match (n,q) with
| (0,q) -> q
| (n,Abstraction(body)) -> remove_abstractions (n - 1) body
| _ -> raise (Failure "remove_abstractions")
let rec variable_is_bound ?height:(height = 0) (p : program) =
match p with
| Index(j) -> j = height
| Apply(f,x) -> variable_is_bound ~height:height f || variable_is_bound ~height:height x
| Invented(_,i) -> variable_is_bound ~height:height i
| Primitive(_,_,_) -> false
| Abstraction(b) -> variable_is_bound ~height:(height+1) b
exception ShiftFailure;;
let rec shift_free_variables ?height:(height = 0) shift p = match p with
| Index(j) -> if j < height then p else
if j + shift < 0 then raise ShiftFailure else Index(j + shift)
| Apply(f,x) -> Apply(shift_free_variables ~height:height shift f,
shift_free_variables ~height:height shift x)
| Invented(_,_) -> p
| Primitive(_,_,_) -> p
| Abstraction(b) -> Abstraction(shift_free_variables ~height:(height+1) shift b)
let rec free_variables ?d:(d=0) e = match e with
| Index(j) -> if j >= d then [j - d] else []
| Apply(f,x) -> free_variables ~d:d f @ free_variables ~d:d x
| Abstraction(b) -> free_variables ~d:(d + 1) b
| _ -> []
let rec substitute i v e =
match e with
| Index(j) ->
if i = j then v else e
| Abstraction(b) ->
Abstraction(substitute (i + 1) (shift_free_variables 1 v) b)
| Apply(f,x) ->
Apply(substitute i v f, substitute i v x)
| _ -> e
let rec beta_normal_form ?reduceInventions:(reduceInventions=false) e =
let rec step = function
| Abstraction(b) -> begin
match step b with
| Some(b') -> Some(Abstraction(b'))
| None -> None
end
| Invented(_,b) when reduceInventions -> Some(b)
| Apply(f,x) -> begin
match step f with
| Some(f') -> Some(Apply(f',x))
| None -> match step x with
| Some(x') -> Some(Apply(f,x'))
| None -> match f with
| Abstraction(body) -> Some(shift_free_variables ~height:0 (-1)
(substitute 0 (shift_free_variables 1 x) body))
| _ -> None
end
| _ -> None
in
match step e with
| None -> e
| Some(e') -> beta_normal_form ~reduceInventions e'
let unit_reference = ref ()
let rec strip_primitives = function
| Index(n) -> Index(n)
| Invented(t, e) -> Invented(t, strip_primitives e)
| Apply(f,x) -> Apply(strip_primitives f, strip_primitives x)
| Abstraction(b) -> Abstraction(strip_primitives b)
| Primitive(t,n,_) -> Primitive(t,n,unit_reference)
(* PRIMITIVES *)
let [@warning "-20"] primitive ?manualLaziness:(manualLaziness = false)
(name : string) (t : tp) x =
let number_of_arguments = arguments_of_type t |> List.length in
(* Force the arguments *)
let x = if manualLaziness then x else magical @@
match number_of_arguments with
| 0 -> magical x
| 1 -> fun a -> (magical x) (Lazy.force a)
| 2 -> fun a -> fun b -> (magical x) (Lazy.force a) (Lazy.force b)
| 3 -> fun a -> fun b -> fun c -> (magical x) (Lazy.force a) (Lazy.force b) (Lazy.force c)
| 4 -> fun a -> fun b -> fun c -> fun d -> (magical x) (Lazy.force a) (Lazy.force b) (Lazy.force c) (Lazy.force d)
| 5 -> fun a -> fun b -> fun c -> fun d -> fun e -> (magical x) (Lazy.force a) (Lazy.force b) (Lazy.force c) (Lazy.force d) (Lazy.force e)
| 6 -> fun a -> fun b -> fun c -> fun d -> fun e -> fun f -> (magical x) (Lazy.force a) (Lazy.force b) (Lazy.force c) (Lazy.force d) (Lazy.force e) (Lazy.force f)
| 7 -> fun a -> fun b -> fun c -> fun d -> fun e -> fun f -> fun g -> (magical x) (Lazy.force a) (Lazy.force b) (Lazy.force c) (Lazy.force d) (Lazy.force e) (Lazy.force f) (Lazy.force g)
| 8 -> fun a -> fun b -> fun c -> fun d -> fun e -> fun f -> fun g -> fun h -> (magical x) (Lazy.force a) (Lazy.force b) (Lazy.force c) (Lazy.force d) (Lazy.force e) (Lazy.force f) (Lazy.force g) (Lazy.force h)
| _ ->
raise (Failure (Printf.sprintf "Primitive %s can not be lazy because it has %d arguments. Change `primitive` in program.ml if you want to enable laziness for %s.\n"
name number_of_arguments name))
in
let p = Primitive(t,name, ref (magical x)) in
assert (not (Hashtbl.mem every_primitive name));
ignore(Hashtbl.add every_primitive name p);
p
(* let primitive_empty_string = primitive "emptyString" tstring "";; *)
let primitive_uppercase = primitive "caseUpper" (tcharacter @> tcharacter) Char.uppercase;;
(* let primitive_uppercase = primitive "strip" (tstring @> tstring) (fun s -> String.strip s);; *)
let primitive_lowercase = primitive "caseLower" (tcharacter @> tcharacter) Char.lowercase;;
let primitive_character_equal = primitive "char-eq?" (tcharacter @> tcharacter @> tboolean) Char.equal;;
let primitive_character_equal = primitive "char-upper?" (tcharacter @> tboolean) Char.is_uppercase;;
let primitive_character_equal = primitive "str-eq?" (tlist tcharacter @> tlist tcharacter @> tboolean) (fun x y -> x = y);;
(* let primitive_capitalize = primitive "caseCapitalize" (tstring @> tstring) String.capitalize;;
* let primitive_concatenate = primitive "concatenate" (tstring @> tstring @> tstring) ( ^ );; *)
let primitive_constant_strings = [primitive "','" tcharacter ',';
primitive "'.'" tcharacter '.';
primitive "'@'" tcharacter '@';
primitive "SPACE" tcharacter ' ';
primitive "'<'" tcharacter '<';
primitive "'>'" tcharacter '>';
primitive "'/'" tcharacter '/';
primitive "'|'" tcharacter '|';
primitive "'-'" tcharacter '-';
primitive "LPAREN" tcharacter '(';
primitive "RPAREN" tcharacter ')';
];;
(* let primitive_slice_string = primitive "slice-string" (tint @> tint @> tstring @> tstring)
* (fun i j s ->
* let i = i + (if i < 0 then String.length s else 0) in
* let j = j + (if j < 0 then 1 + String.length s else 0) in
* String.sub s ~pos:i ~len:(j - i));;
* let primitive_nth_string = primitive "nth" (tint @> tlist tstring @> tstring)
* (fun n words ->
* let n = n + (if n < 0 then List.length words else 0) in
* List.nth_exn words n);;
* let primitive_map_string = primitive "map-string" ((tstring @> tstring) @> tlist tstring @> tlist tstring)
* (fun f l -> List.map ~f:f l);;
* let primitive_string_split = primitive "split" (tcharacter @> tstring @> tlist tstring)
* (fun d x -> String.split ~on:d x);;
* let primitive_string_join = primitive "join" (tstring @> tlist tstring @> tstring)
* (fun d xs -> join ~separator:d xs);;
* let primitive_character_to_string = primitive "chr2str" (tcharacter @> tstring) (String.of_char);; *)
let primitive0 = primitive "0" tint 0;;
let primitive1 = primitive "1" tint 1;;
let primitiven1 = primitive "-1" tint (0-1);;
let primitive2 = primitive "2" tint 2;;
let primitive3 = primitive "3" tint 3;;
let primitive4 = primitive "4" tint 4;;
let primitive5 = primitive "5" tint 5;;
let primitive6 = primitive "6" tint 6;;
let primitive7 = primitive "7" tint 7;;
let primitive8 = primitive "8" tint 8;;
let primitive9 = primitive "9" tint 9;;
let primitive20 = primitive "ifty" tint 20;;
let primitive_addition = primitive "+" (tint @> tint @> tint) (fun x y -> x + y);;
let primitive_increment = primitive "incr" (tint @> tint) (fun x -> 1+x);;
let primitive_decrement = primitive "decr" (tint @> tint) (fun x -> x - 1);;
let primitive_subtraction = primitive "-" (tint @> tint @> tint) (-);;
let primitive_negation = primitive "negate" (tint @> tint) (fun x -> 0-x);;
let primitive_multiplication = primitive "*" (tint @> tint @> tint) ( * );;
let primitive_modulus = primitive "mod" (tint @> tint @> tint) (fun x y -> x mod y);;
let primitive_apply = primitive "apply" (t1 @> (t1 @> t0) @> t0) (fun x f -> f x);;
let primitive_true = primitive "true" tboolean true;;
let primitive_false = primitive "false" tboolean false;;
let primitive_if = primitive "if" (tboolean @> t0 @> t0 @> t0)
~manualLaziness:true
(fun p x y -> if Lazy.force p then Lazy.force x else Lazy.force y);;
let primitive_is_square = primitive "is-square" (tint @> tboolean)
(fun x ->
let y = Float.of_int x in
let s = sqrt y |> Int.of_float in
s*s = x);;
let primitive_is_prime = primitive "is-prime" (tint @> tboolean)
(fun x -> List.mem ~equal:(=) [2; 3; 5; 7; 11; 13; 17; 19; 23; 29; 31; 37; 41; 43; 47; 53; 59; 61; 67; 71; 73; 79; 83; 89; 97; 101; 103; 107; 109; 113; 127; 131; 137; 139; 149; 151; 157; 163; 167; 173; 179; 181; 191; 193; 197; 199] x);;
let primitive_cons = primitive "cons" (t0 @> tlist t0 @> tlist t0) (fun x xs -> x :: xs);;
let primitive_car = primitive "car" (tlist t0 @> t0) (fun xs -> List.hd_exn xs);;
let primitive_cdr = primitive "cdr" (tlist t0 @> tlist t0) (fun xs -> List.tl_exn xs);;
let primitive_is_empty = primitive "empty?" (tlist t0 @> tboolean)
(function | [] -> true
| _ -> false);;
let primitive_string_constant = primitive "STRING" (tlist tcharacter) ();;
let rec substitute_string_constants (alternatives : char list list) e = match e with
| Primitive(c,"STRING",_) -> alternatives |> List.map ~f:(fun a -> Primitive(c,"STRING",ref a |> magical))
| Primitive(_,_,_) -> [e]
| Invented(_,b) -> substitute_string_constants alternatives b
| Apply(f,x) -> substitute_string_constants alternatives f |> List.map ~f:(fun f' ->
substitute_string_constants alternatives x |> List.map ~f:(fun x' ->
Apply(f',x'))) |> List.concat
| Abstraction(b) -> substitute_string_constants alternatives b |> List.map ~f:(fun b' ->
Abstraction(b'))
| Index(_) -> [e]
let rec number_of_string_constants = function
| Primitive(_,"STRING",_) -> 1
| Primitive(_,_,_) -> 0
| Invented(_,b) | Abstraction(b) -> number_of_string_constants b
| Apply(f,x) -> number_of_string_constants f + number_of_string_constants x
| Index(_) -> 0
let rec string_constants_length = function
| Primitive(_,"STRING",v) ->
let v = magical v in
List.length (!v)
| Primitive(_,_,_) -> 0
| Invented(_,b) | Abstraction(b) -> string_constants_length b
| Apply(f,x) -> string_constants_length f + string_constants_length x
| Index(_) -> 0
let rec number_of_real_constants = function
| Primitive(_,"REAL",_) -> 1
| Primitive(_,_,_) -> 0
| Invented(_,b) | Abstraction(b) -> number_of_real_constants b
| Apply(f,x) -> number_of_real_constants f + number_of_real_constants x
| Index(_) -> 0
let rec number_of_free_parameters = function
| Primitive(_,"REAL",_) | Primitive(_,"STRING",_) | Primitive(_,"r_const",_) -> 1
| Primitive(_,_,_) -> 0
| Invented(_,b) | Abstraction(b) -> number_of_free_parameters b
| Apply(f,x) -> number_of_free_parameters f + number_of_free_parameters x
| Index(_) -> 0
let primitive_empty = primitive "empty" (tlist t0) [];;
let primitive_range = primitive "range" (tint @> tlist tint) (fun x -> 0 -- (x-1));;
let primitive_sort = primitive "sort" (tlist tint @> tlist tint) (List.sort ~compare:(fun x y -> x - y));;
let primitive_reverse = primitive "reverse" (tlist tint @> tlist tint) (List.rev);;
let primitive_append = primitive "append" (tlist t0 @> tlist t0 @> tlist t0) (@);;
let primitive_singleton = primitive "singleton" (tint @> tlist tint) (fun x -> [x]);;
let primitive_slice = primitive "slice" (tint @> tint @> tlist tint @> tlist tint) slice;;
let primitive_length = primitive "length" (tlist t0 @> tint) (List.length);;
let primitive_map = primitive "map" ((t0 @> t1) @> (tlist t0) @> (tlist t1)) (fun f l -> List.map ~f:f l);;
let primitive_fold_right = primitive "fold_right" ((tint @> tint @> tint) @> tint @> (tlist tint) @> tint) (fun f x0 l -> List.fold_right ~f:f ~init:x0 l);;
let primitive_mapi = primitive "mapi" ((tint @> t0 @> t1) @> (tlist t0) @> (tlist t1)) (fun f l ->
List.mapi l ~f:f);;
let primitive_a2 = primitive "++" ((tlist t0) @> (tlist t0) @> (tlist t0)) (@);;
let primitive_reducei = primitive "reducei" ((tint @> t1 @> t0 @> t1) @> t1 @> (tlist t0) @> t1) (fun f x0 l -> List.foldi ~f:f ~init:x0 l);;
let primitive_filter = primitive "filter" ((t0 @> tboolean) @> (tlist t0) @> (tlist t0)) (fun f l -> List.filter ~f:f l);;
let primitive_filter_int = primitive "filter_int" ((tint @> tboolean) @> (tlist tint) @> (tlist tint)) (fun f l -> List.filter ~f:f l);;
let primitive_equal = primitive "eq?" (tint @> tint @> tboolean) (fun (a : int) (b : int) -> a = b);;
let primitive_equal0 = primitive "eq0" (tint @> tboolean) (fun (a : int) -> a = 0);;
let primitive_not = primitive "not" (tboolean @> tboolean) (not);;
let primitive_and = primitive "and" (tboolean @> tboolean @> tboolean) (fun x y -> x && y);;
let primitive_nand = primitive "nand" (tboolean @> tboolean @> tboolean) (fun x y -> not (x && y));;
let primitive_or = primitive "or" (tboolean @> tboolean @> tboolean) (fun x y -> x || y);;
let primitive_greater_than = primitive "gt?" (tint @> tint @> tboolean) (fun (x: int) (y: int) -> x > y);;
ignore(primitive "take-word" (tcharacter @> tstring @> tstring) (fun c s ->
List.take_while s ~f:(fun c' -> not (c = c'))));;
ignore(primitive "drop-word" (tcharacter @> tstring @> tstring) (fun c s ->
List.drop_while s ~f:(fun c' -> not (c = c')) |> List.tl |> get_some));;
ignore(primitive "abbreviate" (tstring @> tstring) (fun s ->
let rec f = function
| [] -> []
| ' ' :: cs -> f cs
| c :: cs -> c :: f (List.drop_while cs ~f:(fun c' -> not (c' = ' ')))
in f s));;
ignore(primitive "last-word" (tcharacter @> tstring @> tstring)
(fun c s ->
List.rev s |> List.take_while ~f:(fun c' -> not (c = c')) |> List.rev));;
ignore(primitive "replace-character" (tcharacter @> tcharacter @> tstring @> tstring) (fun c1 c2 s ->
s |> List.map ~f:(fun c -> if c = c1 then c2 else c)));;
let primitive_run = primitive
"run"
(tprogram @> tcanvas)
(fun x ->
GeomLib.Plumbing.relist
(GeomLib.Plumbing.run x))
let primitive_just = primitive "just"
(t0 @> tmaybe t0)
(fun x -> Some(x))
let primitive_nothing= primitive "nothing" (tmaybe t0) None
let primitive_nop = primitive "nop" tprogram GeomLib.Plumbing.nop
let primitive_nop2 = primitive "nop2" tprogram GeomLib.Plumbing.nop
let primitive_embed = primitive
"embed"
(tprogram @> tprogram)
GeomLib.Plumbing.embed
let primitive_concat = primitive
"concat"
(tprogram @> tprogram @> tprogram)
GeomLib.Plumbing.concat
let primitive_turn = primitive
"turn"
(tmaybe tvar @> tprogram)
GeomLib.Plumbing.turn
let primitive_define = primitive
"define"
(tvar @> tprogram)
GeomLib.Plumbing.define
let primitive_repeat = primitive
"repeat"
(tmaybe tvar @> tprogram @> tprogram)
GeomLib.Plumbing.repeat
let primitive_line= primitive
"basic_line"
tprogram
GeomLib.Plumbing.basic_line
let primitive_integrate= primitive
"integrate"
(tmaybe tvar @> tboolean @>
(*tmaybe tvar @> tmaybe tvar @>*)
tmaybe tvar @> tmaybe tvar @>
tprogram)
GeomLib.Plumbing.integrate
let var_unit = primitive "var_unit" tvar GeomLib.Plumbing.var_unit
let var_unit = primitive "var_two" tvar GeomLib.Plumbing.var_two
let var_unit = primitive "var_three" tvar GeomLib.Plumbing.var_three
let var_double = primitive "var_double" (tvar @> tvar) GeomLib.Plumbing.var_double
let var_half = primitive "var_half" (tvar @> tvar) GeomLib.Plumbing.var_half
let var_next = primitive "var_next" (tvar @> tvar) GeomLib.Plumbing.var_next
let var_prev = primitive "var_prev" (tvar @> tvar) GeomLib.Plumbing.var_prev
let var_opposite = primitive "var_opposite" (tvar @> tvar) GeomLib.Plumbing.var_opposite
let var_opposite = primitive "var_divide" (tvar @> tvar @> tvar) GeomLib.Plumbing.var_divide
let var_name = primitive "var_name" tvar GeomLib.Plumbing.var_name
(* LOGO *)
let logo_RT = primitive "logo_RT" (tangle @> turtle) LogoLib.LogoInterpreter.logo_RT
let logo_FW = primitive "logo_FW" (tlength @> turtle) LogoLib.LogoInterpreter.logo_FW
let logo_SEQ = primitive "logo_SEQ" (turtle @> turtle @> turtle) LogoLib.LogoInterpreter.logo_SEQ
let logo_FWRT = primitive "logo_FWRT"
(tlength @> tangle @> turtle @> turtle)
(fun x y z ->
LogoLib.LogoInterpreter.logo_SEQ
(LogoLib.LogoInterpreter.logo_SEQ
(LogoLib.LogoInterpreter.logo_FW x)
(LogoLib.LogoInterpreter.logo_RT y))
z)
let logo_PU = primitive "logo_PU"
(turtle @> turtle)
(fun x ->
LogoLib.LogoInterpreter.logo_SEQ
LogoLib.LogoInterpreter.logo_PU
x)
let logo_PD = primitive "logo_PD"
(turtle @> turtle)
(fun x ->
LogoLib.LogoInterpreter.logo_SEQ
LogoLib.LogoInterpreter.logo_PD
x);;
primitive "logo_PT"
((turtle @> turtle) @> (turtle @> turtle))
(fun body continuation ->
LogoLib.LogoInterpreter.logo_GET (fun state ->
let original_state = state.p in
LogoLib.LogoInterpreter.logo_SEQ
LogoLib.LogoInterpreter.logo_PU
(body (LogoLib.LogoInterpreter.logo_SEQ
(if original_state
then LogoLib.LogoInterpreter.logo_PD else LogoLib.LogoInterpreter.logo_PU)
continuation))))
let logo_GET = primitive "logo_GET"
(tstate @> turtle @> turtle)
(fun f -> (LogoLib.LogoInterpreter.logo_GET f))
let logo_SET = primitive "logo_SET"
(tstate @> turtle @> turtle)
(fun s -> fun z ->
LogoLib.LogoInterpreter.logo_SEQ
(LogoLib.LogoInterpreter.logo_SET s)
z)
let logo_GETSET = primitive "logo_GETSET"
((turtle @> turtle) @> turtle @> turtle)
(fun t -> fun z ->
(LogoLib.LogoInterpreter.logo_GET
(fun s ->
t
(LogoLib.LogoInterpreter.logo_SEQ
(LogoLib.LogoInterpreter.logo_SET s)
z)
)))
(* let logo_GETSET = primitive "logo_GETSET" *)
(* (turtle @> turtle @> turtle) *)
(* (fun t -> fun k -> *)
(* (LogoLib.LogoInterpreter.logo_GET *)
(* (fun s -> *)
(* (LogoLib.LogoInterpreter.logo_SEQ *)
(* t *)
(* (LogoLib.LogoInterpreter.logo_SEQ *)
(* (LogoLib.LogoInterpreter.logo_SET s) *)
(* k) *)
(* ) *)
(* ) *)
(* ) *)
(* ) *)
let logo_S2A = primitive "logo_UA" (tangle) (1.)
let logo_S2A = primitive "logo_UL" (tlength) (1.)
let logo_S2A = primitive "logo_ZA" (tangle) (0.)
let logo_S2A = primitive "logo_ZL" (tlength) (0.)
let logo_IFTY = primitive "logo_IFTY" (tint) (20)
let logo_IFTY = primitive "logo_epsL" (tlength) (0.05)
let logo_IFTY = primitive "logo_epsA" (tangle) (0.025)
let logo_IFTY = primitive "line"
(turtle @> turtle)
(fun z ->
LogoLib.LogoInterpreter.logo_SEQ
(LogoLib.LogoInterpreter.logo_SEQ
(LogoLib.LogoInterpreter.logo_FW 1.)
(LogoLib.LogoInterpreter.logo_RT 0.))
z)
let logo_DIVA = primitive "logo_DIVA"
(tangle @> tint @> tangle)
(fun a b -> a /. (float_of_int b) )
let logo_DIVA = primitive "logo_MULA"
(tangle @> tint @> tangle)
(fun a b -> a *. (float_of_int b) )
let logo_DIVA = primitive "logo_DIVL"
(tlength @> tint @> tlength)
(fun a b -> a /. (float_of_int b) )
let logo_DIVA = primitive "logo_MULL"
(tlength @> tint @> tlength)
(fun a b -> a *. (float_of_int b) )
let logo_ADDA = primitive "logo_ADDA" (tangle @> tangle @> tangle) ( +. )
let logo_SUBA = primitive "logo_SUBA" (tangle @> tangle @> tangle) ( -. )
let logo_ADDL = primitive "logo_ADDL" (tlength @> tlength @> tlength) ( +. )
let logo_SUBL = primitive "logo_SUBL" (tlength @> tlength @> tlength) ( -. )
let _ = primitive "logo_forLoop"
(tint @> (tint @> turtle @> turtle) @> turtle @> turtle)
(fun i f z -> List.fold_right (0 -- (i-1)) ~f ~init:z)
let _ = primitive "logo_forLoopM"
(tint @> (tint @> turtle) @> turtle @> turtle)
(fun n body k0 ->
((List.map (0 -- (n-1)) ~f:body))
|> List.fold_right
~f:(LogoLib.LogoInterpreter.logo_SEQ)
~init:k0
)
(*let logo_CHEAT = primitive "logo_CHEAT" (ttvar @> turtle) LogoLib.LogoInterpreter.logo_CHEAT*)
(*let logo_CHEAT2 = primitive "logo_CHEAT2" (ttvar @> turtle) LogoLib.LogoInterpreter.logo_CHEAT2*)
(*let logo_CHEAT3 = primitive "logo_CHEAT3" (ttvar @> turtle) LogoLib.LogoInterpreter.logo_CHEAT3*)
(*let logo_CHEAT4 = primitive "logo_CHEAT4" (ttvar @> turtle) LogoLib.LogoInterpreter.logo_CHEAT4*)
let default_recursion_limit = 20;;
let rec unfold x p h n =
if p x then [] else h x :: unfold (n x) p h n
let primitive_unfold = primitive "unfold" (t0 @> (t0 @> tboolean) @> (t0 @> t1) @> (t0 @> t0) @> tlist t1) unfold;;
let primitive_index = primitive "index" (tint @> tlist t0 @> t0) (fun j l -> List.nth_exn l j);;
let primitive_zip = primitive "zip" (tlist t0 @> tlist t1 @> (t0 @> t1 @> t2) @> tlist t2)
(fun x y f -> List.map2_exn x y ~f:f);;
let primitive_fold = primitive "fold" (tlist t0 @> t1 @> (t0 @> t1 @> t1) @> t1)
(fun l x0 f -> List.fold_right ~f:f ~init:x0 l);;
let default_recursion_limit = ref 50;;
let set_recursion_limit l = default_recursion_limit := l;;
exception RecursionDepthExceeded of int;;
let fixed_combinator argument body =
(* strict with respect to body but lazy with respect argument *)
(* body expects to be passed 2 thunks *)
let body = Lazy.force body in
let recursion_limit = ref !default_recursion_limit in
let rec fix x =
(* r is just a wrapper over fix that counts the number of
recursions *)
let r z =
decr recursion_limit;
if !recursion_limit > 0 then fix z
else raise (RecursionDepthExceeded(!default_recursion_limit))
in
body (lazy r) x
in
fix argument
let fixed_combinator2 argument1 argument2 body =
let body = Lazy.force body in
let recursion_limit = ref !default_recursion_limit in
let rec fix x y =
let r a b =
decr recursion_limit;
if !recursion_limit > 0 then
fix a b
else raise (RecursionDepthExceeded(!default_recursion_limit))
in body (lazy r) x y
in
fix argument1 argument2 (* (lazy argument1) (lazy argument2) *)
let primitive_recursion =
primitive ~manualLaziness:true "fix1" (t0 @> ((t0 @> t1) @> (t0 @> t1)) @> t1)
fixed_combinator;;
let primitive_recursion2 =
primitive ~manualLaziness:true "fix2" (t0 @> t1 @> ((t0 @> t1 @> t2) @> (t0 @> t1 @> t2)) @> t2)
fixed_combinator2;;
let is_recursion_of_arity a = function
| Primitive(_,n,_) -> ("fix"^(Int.to_string a)) = n
| _ -> false
let is_recursion_primitive = function
| Primitive(_,"fix1",_) -> true
| Primitive(_,"fix2",_) -> true
| _ -> false
let program_parser : program parsing =
let token = token_parser (fun c -> Char.is_alphanum c || List.mem ~equal:( = )
['_';'-';'?';'/';'.';'*';'\'';'+';',';
'>';'<';'@';'|';] c) in
let whitespace = token_parser ~can_be_empty:true Char.is_whitespace in
let number = token_parser Char.is_digit in
let primitive = token %% (fun name ->
try
return_parse (lookup_primitive name)
with _ ->
(* Printf.printf "Error finding type of primitive %s\n" name; *)
parse_failure)
in
let variable : program parsing = constant_parser "$" %% (fun _ ->
number%%(fun n -> Index(Int.of_string n) |> return_parse))
in
let fixed_real : program parsing = constant_parser "real" %% (fun _ ->
token %% (fun v ->
let v = v |> Float.of_string in
Primitive(treal, "real", ref (v |> magical)) |> return_parse))
in
let rec program_parser () : program parsing =
(application () <|> primitive <|> variable <|> invented() <|> abstraction() <|> fixed_real)
and invented() =
constant_parser "#" %% (fun _ ->
program_parser()%%(fun p ->
let t =
try
infer_program_type empty_context [] p |> snd
with UnificationFailure | UnboundVariable -> begin
Printf.printf "WARNING: Could not type check invented %s\n" (string_of_program p);
t0
end
in
return_parse (Invented(t,p))))
and abstraction() =
let rec nabstractions n b =
if n = 0 then b else nabstractions (n-1) (Abstraction(b))
in
constant_parser "(lambda"%%(fun _ ->
whitespace%%(fun _ ->
program_parser()%%(fun b ->
constant_parser ")"%%(fun _ ->
return_parse (Abstraction(b)))))
<|>
number%%(fun n -> whitespace%%(fun _ ->
program_parser()%%(fun b ->
constant_parser ")"%%(fun _ ->
return_parse (nabstractions (Int.of_string n) b))))))
and application_sequence (maybe_function : program option) : program parsing =
whitespace%%(fun _ ->
match maybe_function with
| None -> (* cannot terminate sequence because there is nothing before it *)
program_parser () %%(fun f -> application_sequence (Some(f)))
| Some(f) ->
(return_parse f) <|> (program_parser () %%(fun x -> application_sequence (Some(Apply(f,x))))))
and application () =
constant_parser "(" %% (fun _ ->
application_sequence None %% (fun a ->
constant_parser ")" %% (fun _ ->
return_parse a)))
in
program_parser ()
let parse_program s = run_parser program_parser s
(* let test_program_inference program desired_type =
* let (context,t) = infer_program_type empty_context [] program in
* let t = applyContext context t in
* let t = canonical_type t in
* Printf.printf "%s : %s\n" (string_of_program program) (string_of_type t);
* assert (t = (canonical_type desired_type))
*
* let program_test_cases() =
* test_program_inference (Abstraction(Index(0))) (t0 @> t0);
* test_program_inference (Abstraction(Abstraction(Apply(Index(0),Index(1))))) (t0 @> (t0 @> t1) @> t1);
* test_program_inference (Abstraction(Abstraction(Index(1)))) (t0 @> t1 @> t0);
* test_program_inference (Abstraction(Abstraction(Index(0)))) (t0 @> t1 @> t1);
* let v : int = evaluate [] (Apply(primitive_increment, primitive0)) in
* Printf.printf "%d\n" v;
*
* ;; *)
let parsing_test_case s =
Printf.printf "Parsing the string %s\n" s;
program_parser (s,0) |> List.iter ~f:(fun (p,n) ->
if n = String.length s then
(Printf.printf "Parsed into the program: %s\n" (string_of_program p);
assert (s = (string_of_program p));
flush_everything())
else
(Printf.printf "With the suffix %n, we get the program %s\n" n (string_of_program p);
flush_everything()));
Printf.printf "\n"
;;
let parsing_test_cases() =
parsing_test_case "(+ 1)";
parsing_test_case "($0 $1)";
parsing_test_case "(+ 1 $0 $2)";
parsing_test_case "(map (+ 1) $0 $1)";
parsing_test_case "(map (+ 1) ($0 (+ 1) (- 1) (+ -)) $1)";
parsing_test_case "(lambda $0)";
parsing_test_case "(lambda (+ 1 #(* 8 1)))";
parsing_test_case "(lambda (+ 1 #(* 8 map)))";
;;
(* parsing_test_cases();; *)
(* program_test_cases();; *)
let [@warning "-20"] performance_test_case() =
let e = parse_program "(lambda (fix1 $0 (lambda (lambda (if (empty? $0) $0 (cons (* 2 (car $0)) ($1 (cdr $0))))))))" |> get_some in
let xs = [2;1;9;3;] in
let n = 10000000 in
time_it "evaluate program many times" (fun () ->
(0--n) |> List.iter ~f:(fun j ->
if j = n then
Printf.printf "%s\n" (evaluate [] e xs |> List.map ~f:Int.to_string |> join ~separator:" ")
else
ignore (evaluate [] e xs)));
let c = analyze_evaluation e [] in
time_it "evaluate analyzed program many times" (fun () ->
(0--n) |> List.iter ~f:(fun j ->
if j = n then
Printf.printf "%s\n" (c xs |> List.map ~f:Int.to_string |> join ~separator:" ")
else
ignore(c xs)))
;;
(* performance_test_case();; *)
(* let recursion_test_case() =
* let f zs = fixed_combinator zs (fun r l ->
* match l with
* | [] -> []
* | x::xs -> x*2 :: r xs) in
* f (0--18) |> List.map ~f:Int.to_string |> join ~separator:" " |> Printf.printf "%s\n";
* f (0--10) |> List.map ~f:Int.to_string |> join ~separator:" " |> Printf.printf "%s\n";
* f (0--2) |> List.map ~f:Int.to_string |> join ~separator:" " |> Printf.printf "%s\n";
* let e = parse_program "(lambda (fix1 (lambda (lambda (if (empty? $0) $0 (cons (\* 2 (car $0)) ($1 (cdr $0)))))) $0))" |> get_some in
* Printf.printf "%s\n" (string_of_program e);
* evaluate [] e [1;2;3;4;] |> List.map ~f:Int.to_string |> join ~separator:" " |> Printf.printf "%s\n";
*
* let e = parse_program "(lambda (lambda (fix2 (lambda (lambda (lambda (if (empty? $1) $0 (cons (car $1) ($2 (cdr $1) $0)))))) $0 $1)))" |> get_some in
* infer_program_type empty_context [] e |> snd |> string_of_type |> Printf.printf "%s\n";
* evaluate [] e (0--4) [9;42;1] |> List.map ~f:Int.to_string |> join ~separator:" " |> Printf.printf "%s\n" *)
(* recursion_test_case();; *)
(* let timeout_test_cases() = *)
(* let list_of_numbers = [ *)
(* "(lambda (fix (lambda (lambda (if (empty? $0) $0 (cons (\* 2 (car $0)) ($1 (cdr $0)))))) $0))"; *)
(* ] in *)
(* let list_of_numbers = list_of_numbers |> List.map ~f:(analyze_evaluation%get_some%parse_program) in *)
(* let xs = [(0--10);(0--10);(0--10)] in *)
(* time_it "evaluated all of the programs" (fun () -> *)
(* let () = *)
(* let e = parse_program "(lambda (reducei (lambda (lambda (lambda (range $0)))) empty $0))" |> get_some in *)
(* Printf.printf "tp = %s\n" (string_of_type @@ snd @@ infer_program_type empty_context [] e); *)
(* let f = evaluate [] e in *)
(* f [1;2]; *)
(* List.foldi [1;3;2;] ~init:[] ~f:(fun x y z -> 0--z) |> List.iter ~f:(fun a -> *)
(* Printf.printf "%d\n" a) *)
(* let () = *)
(* let e = parse_program "(lambda (lambda (- $1 $0)))" |> get_some in *)
(* Printf.printf "%d\n" (run_with_arguments e [1;9]) *)
let test_lazy_evaluation() =
let ps = ["1";"0";"(+ 1 1)";
"(lambda (+ $0 2))"; "(+ 5)";
"-"; "(lambda2 (- $0 $1))";
"((lambda 1) (car empty))";
"((lambda $0) 9)";
"((lambda ($0 ($0 ($0 1)))) (lambda (+ $0 $0)))";
"((lambda (lambda (if (eq? $0 0) $1 (+ $1 $1)))) 5 1)";
"((lambda2 (if (eq? $0 0) $1 (+ $1 $1))) 5 0)";
"(car (cdr (cons 1 (cons 2 (cons 3 empty)))))";
"(cdr (cons 1 (cons 2 (cons 3 empty))))";
"(map (+ 1) (cons 1 (cons 2 (cons 3 empty))))";
"(map (+ 1) (cons 1 (cons 2 (cons 3 empty))))";
"(map (lambda (+ $0 $0)) (cons 1 (cons 2 (cons 3 empty))))";
"(fold_right (lambda2 (+ $0 $1)) 0 (cons 1 (cons 2 (cons 3 empty))))";
"(fix1 (cons 1 (cons 2 (cons 3 empty))) (lambda2 (if (empty? $0) 0 (+ 1 ($1 (cdr $0))))))";
"(fix1 (cons 1 (cons 2 (cons 3 empty))) (lambda2 (if (empty? $0) 0 (+ (car $0) ($1 (cdr $0))))))";
"(fix2 5 7 (lambda (lambda (lambda (if (eq? $0 0) 0 (+ $1 ($2 $1 (- $0 1))))))))"] in