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(* Copyright Jeremy Yallop 2007.
This file is free software, distributed under the MIT license.
See the file COPYING for details.
*)
(* Interned strings *)
module StringMap = Map.Make(String)
(* global state *)
let map = ref StringMap.empty
let counter = ref 0
type t = int * string
deriving (Show)
let intern s =
try StringMap.find s !map
with Not_found ->
let fresh = (!counter, String.copy s) in begin
map := StringMap.add s fresh !map;
incr counter;
fresh
end
let to_string (_,s) = String.copy s
let name = snd
let compare (l,_) (r,_) = compare l r
let eq (l,_) (r,_) = l = r
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