heh/env.ml at master · ashinkarov/heh

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* purpose with or without fee is hereby granted, provided that the above

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* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY

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* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM

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exception EnvFailure of string

type env = (string * string) list;;

let env_new: unit -> env = fun () ->

[]

let env_add e v p =

(v, p) :: e

let rec env_lookup e v =

match e with

| [] -> raise (EnvFailure

(Printf.sprintf "lookup of variable `%s' failed" v))

| (v', p') :: tl ->

if v' = v then

else

env_lookup tl v

let env_to_str e =

if List.length e = 0 then

"[]"

else

String.concat ", " (List.map (fun vp ->

let v, p = vp in

Printf.sprintf "%s |-> %s" v p) e)