kraken/partial_eval.kp

(with_import "./collections.kp"
(let (
    ; This partial eval only works via the root env,
    ; since we can't tell from outside if something takes an env
    ; or not
    ; Also, based on that, we have to switch on every primitive...


    ; Here is every form in k'
    ; True
    ; False
    ; Env: *KPEnv
    ; Combiner: KPCombiner / BuiltinCombiner: KPBuiltinCombiner
    ; String: str
    ; Symbol: str
    ; Int: int
    ; Array: rc<vec<KPValue>>
    ; Nil


    ; Ok, some more things we need / need to change

    ; Arrays need to be able to contain some combination of now and later that 
    ; can be extracted correctly by the relevent operators (idx, slice)

    ; Vau needs to be handled, obv, which will require a handling of it
    ; pre-evaluating the parameters. The more I think about it, the more
    ; straight forward it seems actually - it can mostly mirror actual vau?

    ; how should empty-env be handled? More generally, how much do we reify enviornments?

    ; meta...

    ; I think now/later will have to be split into
    ; later/now_value/array/comb(wrap_level / dynamic_env_usage?)/env
    ; Env will need special checking for escaping, including when contained inside of an array or other combinator
    ; Actually, that extends to checking escaping for combinators in general, since they may close over laters

    ; Ok, instead of just ['now v] and ['later v], we have these marked values
    ; ['val v] (v can be an array)
    ; ['later c]
    ; ['marked_array a] (a contains marked values)
    ; ['comb wrap_level de? se params body <actual_function>]
    ; ['prim_comb <handler_function> <actual_function>]
    ; ['env [ ['symbol marked_value ]... ] <name_it_can_be_found_as(changes, must not escape)>]


    val? (lambda (x) (= 'val (idx x 0)))
    .val (lambda (x) (idx x 1))
    later? (lambda (x) (= 'later (idx x 0)))
    .later (lambda (x) (idx x 1))
    marked_array? (lambda (x) (= 'marked_array (idx x 0)))
    comb? (lambda (x) (= 'comb (idx x 0)))
    .comb (lambda (x) (slice x 1 -1))
    prim_comb? (lambda (x) (= 'prim_comb (idx x 0)))
    .prim_comb (lambda (x) (idx x 1))
    marked_env? (lambda (x) (= 'env (idx x 0)))

    strip (rec-lambda recurse (x)
        (cond (val? x)          (.val x)
              (later? x)        (.later x)
              (marked_array? x) (map recurse (idx x 1))
              (comb? x)         (idx x 6)
              (prim_comb? x)    (idx x 2)
              (makred_env? x)   (error "Env escaped to strip!")
        )
    )

    ; partial_eval_helper always takes in unmarked expressions and makes marked ones, maintaining marked envs
    partial_eval_helper (rec-lambda recurse (x env)
        (cond   (= x true)                      ['val true ]
                (= x false)                     ['val false]
                (env? x)                        (error "called partial_eval with an env " x)
                (combiner? x)                   (error "called partial_eval with a combiner, not yet supported (assuming just parsed symbols etc) " x)
                (string? x)                     ['val x]
                (symbol? x)                     (get-value env x)
                (int? x)                        ['val x]
                (and (array? x) (= 0 (len x)))  (error "Partial eval on empty array")
                (array? x)                      (let ( comb (recurse (idx x 0) env) )
                                                     (cond (later? comb)     ['later x]
                                                           (prim_comb? comb) ((.prim_comb comb) env (slice x 1 -1))
                                                           (comb? comb)      (let (
                                                                                 [wrap_level de? se params body actual_function] (.comb comb)
                                                                                 ;subs (map (lambda (y) (recurse y env)) x)
                                                                             ) ['later x])
                                                           true              (error (str "Partial eval noticed that you will likely call not a function " x))))
                (nil? x)                        ['val x]

        )
    )
    needs_params_val_lambda (vau de (f_sym) (let (
        actual_function (eval f_sym de)
        handler (lambda (de params) (let (evaled_params (map (lambda (x) (partial_eval_helper x de)) params))
                                         (if (foldl (lambda (a x) (and a (val? x))) true evaled_params) ['val (lapply actual_function (map .val evaled_params))]
                                                                                                        ['later (cons actual_function params)])))
        ) [f_sym ['prim_comb handler actual_function]]))

    partial_eval (lambda (x) (partial_eval_helper x [
        ; vau
        ; eval
        ; cond
        (needs_params_val_lambda symbol?)
        (needs_params_val_lambda int?)
        (needs_params_val_lambda string?)
        ; combiner?
        ; env?
        (needs_params_val_lambda nil?)
        (needs_params_val_lambda bool?)
        ; array?
        (needs_params_val_lambda str-to-symbol)
        (needs_params_val_lambda get-text)
        ; array
        ; len
        ; idx
        ; slice
        ; concat
        (needs_params_val_lambda +)
        (needs_params_val_lambda -)
        (needs_params_val_lambda *)
        (needs_params_val_lambda /)
        (needs_params_val_lambda %)
        (needs_params_val_lambda &)
        (needs_params_val_lambda |)
        (needs_params_val_lambda <<)
        (needs_params_val_lambda >>)
        (needs_params_val_lambda =)
        (needs_params_val_lambda !=)
        (needs_params_val_lambda <)
        (needs_params_val_lambda <=)
        (needs_params_val_lambda >)
        (needs_params_val_lambda >=)

        ; Don't forget, these short-circut with the truthy/falsey values
        ; and
        ; or

        ; pr-str
        (needs_params_val_lambda str)
        (needs_params_val_lambda prn)
        ; println
        ; meta
        ; with-meta
        ; wrap
        ; unwrap
        ; error
        ; recover
        ; read-string
        ; slurp
        ; get_line
        ; write_file
        ; empty_env
    ]))
)
    (provide partial_eval strip)
))