src/utils/cdk/list2.ml

   1 (* Copyright 2001, 2002 b8_bavard, b8_fee_carabine, INRIA *)
   2 (*
   3     This file is part of mldonkey.
   4
   5     mldonkey is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     mldonkey is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with mldonkey; if not, write to the Free Software
  17     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18 *)
  19
  20 let rec removeq_rec ele list tail =
  21   match list with
  22     [] -> List.rev tail
  23   | e :: list ->
  24       if e == ele then removeq_rec ele list tail
  25       else
  26         removeq_rec ele list (e :: tail)
  27
  28 let rec removeq ele list =
  29   removeq_rec ele list []
  30
  31 let rec remove_rec ele list tail =
  32   match list with
  33     [] -> List.rev tail
  34   | e :: list ->
  35       if e = ele then remove_rec ele list tail
  36       else
  37         remove_rec ele list (e :: tail)
  38
  39 let remove ele list =
  40   remove_rec ele list []
  41
  42 let rec remove_one_rec ele list tail =
  43   match list with
  44     [] -> List.rev tail
  45   | e :: list ->
  46       if e = ele then
  47         List.rev_append tail list
  48       else
  49         remove_one_rec ele list (e :: tail)
  50
  51 let remove_one ele list =
  52   remove_rec ele list []
  53
  54 let rec removeq_first ele list =
  55   match list with
  56     e :: tail when e == ele -> tail
  57   | e :: tail -> e :: (removeq_first ele tail)
  58   | _ -> []
  59
  60 let rec remove_first ele list =
  61   match list with
  62     e :: tail when e = ele -> remove_first ele tail
  63   | e :: tail -> e :: (remove_first ele tail)
  64   | _ -> []
  65
  66 let rec cut_rec n list r =
  67   match n, list with
  68     (0,_) | (_, []) -> List.rev r, list
  69   | _, x :: tail ->
  70       cut_rec (n-1) tail (x :: r)
  71
  72 let cut n list =
  73   if n < 0 then failwith "List2.sub: invalid parameter";
  74   cut_rec n list []
  75
  76 let tail_map f list =
  77   List.rev (List.rev_map f list)
  78
  79
  80 let rec assoc_inv x = function
  81     [] -> raise Not_found
  82   | (a,b)::l -> if b = x then a else assoc_inv x l
  83
  84 let safe_iter f list =
  85   List.iter (fun v -> try f v with _ -> ()) list
  86
  87 let min list =
  88   let rec iter m tail =
  89     match tail with
  90       [] -> m
  91     | m' :: tail ->
  92         iter (min m' m) tail
  93   in
  94   match list with
  95     [] -> raise Not_found
  96   | m :: tail -> iter m tail
  97
  98 let max list =
  99   let rec iter m tail =
 100     match tail with
 101       [] -> m
 102     | m' :: tail ->
 103         iter (max m' m) tail
 104   in
 105   match list with
 106     [] -> raise Not_found
 107   | m :: tail -> iter m tail
 108
 109 let shuffle list =
 110   let a = Array.of_list list in
 111   let len = Array.length a in
 112   for i = 0 to len-1 do
 113     let p = Random.int (len-1) in
 114     let tmp = a.(i) in
 115     a.(i) <- a.(p);
 116     a.(p) <- tmp;
 117   done;
 118   Array.to_list a
 119
 120 let filter_map f =
 121   List.fold_left (fun acc x -> match f x with Some y -> y :: acc | None -> acc) []
 122