Reorganized the standard library a little more, moved the initialization code for the standard environment into a function. Making way for more organization changes to come

This commit is contained in:
2025-11-05 23:55:21 +03:00
parent bafa9bdfbe
commit 724aeefc0f
4 changed files with 97 additions and 91 deletions

View File

@@ -1,16 +1,6 @@
open Ast;;
open InterpreterStdlib;;
let default_env: environment = [Hashtbl.create 1024];;
let add_builtin s f =
Env.set_global default_env s (LBuiltinFunction (s, f))
let add_special s f =
Env.set_global default_env s (LBuiltinSpecial (s, f))
let make_env () = Env.copy default_env
(* the type annotations are unnecessary, but help constrain us from a
potentially more general function here *)
let rec eval_sym (env: environment) (s: string) =
@@ -63,8 +53,6 @@ and eval_apply args = function
| v ->
invalid_arg ("Non-macro non-function value passed to eval_apply "
^ dbg_print_one v)
and eval_call env func args =
match func with
@@ -81,80 +69,8 @@ and eval_call env func args =
| v -> raise (Invalid_argument
(Printf.sprintf "eval_apply: cannot call non-function object %s" (dbg_print_one v)))
(* This only creates a *local* binding, contained to the body given. *)
let bind_local env = function
| LCons (LSymbol s, LCons (v, body)) ->
let e = Env.new_lexical env in
Env.set_local e s v;
eval_body e body
| _ -> invalid_arg "invalid argument to bind-local"
(* special form that creates a global binding *)
let lisp_define env = function
| LCons (LSymbol s, LCons (v, LNil)) ->
let evaluated = eval_one env v in
Env.set_global env s evaluated;
evaluated
| _ -> invalid_arg "invalid args to def"
let lisp_if env = function
| LCons (cond, LCons (if_true, LNil)) ->
(match eval_one env cond with
| LNil -> LNil
| _ -> eval_one env if_true)
| LCons (cond, LCons (if_true, LCons (if_false, LNil))) ->
(match eval_one env cond with
| LNil -> eval_one env if_false
| _ -> eval_one env if_true)
| _ -> invalid_arg "invalid argument list passed to if!"
let eval_all env vs =
let ev v = eval_one env v in
List.map ev vs
let () = add_builtin "+" add
let () = add_builtin "-" sub
let () = add_builtin "car" car
let () = add_builtin "cdr" cdr
let () = add_builtin "cons" cons
let () = add_special "def" lisp_define
let () = add_builtin "set" lisp_set
let () = add_builtin "list" lisp_list
let () = add_special "fn" lambda
let () = add_special "fn-macro" lambda_macro
let () = add_special "let-one" bind_local
let () = add_special "quote" (fun _ -> function
| LCons (x, LNil) -> x
| _ -> invalid_arg "hmm")
let () = add_special "if" lisp_if
let () = add_builtin "nil?" lisp_not
let () = add_builtin "not" lisp_not (* Yes, these are the same thing *)
(*let () = add_builtin "print" lisp_prin *)
(* I know this looks insane. please trust me.
Idea: maybe put this in a file instead of putting
literally the entire standard library in a constant string
*)
let _ = eval_all default_env (Read.parse_str
"
(def defn
(fn-macro (name lm . body)
(list 'def name (cons 'fn (cons lm body)))))
(def defmacro
(fn-macro (name lm . body)
(list 'def name (cons 'fn-macro (cons lm body)))))
(defmacro setq (sym val)
(list 'set (list 'quote sym) val))
(defmacro letfn (sym fun . body)
(cons 'let-one (cons sym (cons '() (cons (list 'setq sym fun) body)))))
List.map ev vs;;
(defn filter (f l)
(letfn helper
(fn (l acc)
(if (nil? l) acc (helper (cdr l) (if (f (car l)) (cons (car l) acc) acc))))
(helper l '())))
")