#ocaml on 2011-02-13 — irc logs at freenode.irclog.whitequark.org

2010-08-02 14:28 gildor changed the topic of #ocaml to: Discussions about the OCaml programming language | http://caml.inria.fr/ | OCaml 3.12.0 http://bit.ly/aNZBUp

00:22 bbc has quit [Quit: Lost terminal]

00:32 kmicinski has joined #ocaml

00:41 boscop has quit [Ping timeout: 240 seconds]

00:42 kmicinski has quit [Quit: leaving]

00:48 ftrvxmtrx has quit [Ping timeout: 250 seconds]

00:52 ulfdoz_ has joined #ocaml

00:56 ulfdoz has quit [Ping timeout: 276 seconds]

00:56 ulfdoz_ is now known as ulfdoz

00:56 alexyk has quit [Quit: alexyk]

00:58 ftrvxmtrx has joined #ocaml

01:05 alexyk has joined #ocaml

01:32 alexyk has quit [Quit: alexyk]

01:35 alexyk has joined #ocaml

01:36 tony_ has quit [Ping timeout: 240 seconds]

01:37 seafood has quit [Ping timeout: 240 seconds]

01:43 alexyk has quit [Quit: alexyk]

01:46 philtor has quit [Ping timeout: 240 seconds]

01:49 mal`` has quit [Quit: Coyote finally caught me]

01:51 mal`` has joined #ocaml

01:53 joewilliams_away is now known as joewilliams

02:07 groovy2shoes has joined #ocaml

02:12 philtor has joined #ocaml

02:14 <philtor> going through the lwt docs...

02:14 <philtor> says to use the toplevel.

02:14 alexyk has joined #ocaml

02:14 joewilliams is now known as joewilliams_away

02:14 <philtor> so this works:

02:15 <philtor> # #use "topfind";;

02:15 <philtor> # #require "lwt";;

02:15 <philtor> But then I try to do this and it doesn't:

02:15 <philtor> # Lwt_io.read_char;;

02:15 <philtor> # Error: Reference to undefined global `Lwt_io'

02:16 <philtor> so the require of "lwt" worked, but couldn't find the Lwt_io module, it seems.

02:17 alexyk has quit [Read error: Connection reset by peer]

02:18 <philtor> I'm running 3.12 and according to godi_console I've got the 2.2.1 version of lwt installed.

02:23 <thelema> philtor: hmm... maybe that's in a different findlib module

02:23 <thelema> at the command line, try ocamlfind list | grep lwt

02:23 <thelema> is there a lwt_io (or lwt.io) package?

02:28 alexyk has joined #ocaml

02:29 alexyk has quit [Read error: Connection reset by peer]

02:33 philtor has quit [Ping timeout: 240 seconds]

02:34 coucou747 has quit [Ping timeout: 255 seconds]

02:38 alexyk has joined #ocaml

02:39 AxleLonghorn has joined #ocaml

02:40 alexyk has quit [Read error: Connection reset by peer]

02:49 alexyk has joined #ocaml

02:55 lopex has quit [Ping timeout: 240 seconds]

03:01 lopex has joined #ocaml

03:03 fraggle_ has quit [Ping timeout: 276 seconds]

03:03 alexyk has quit [Quit: alexyk]

03:04 groovy2shoes has left #ocaml []

03:07 fraggle_ has joined #ocaml

03:10 lopex has quit []

03:17 Amorphous has quit [Ping timeout: 272 seconds]

03:20 alexyk has joined #ocaml

03:24 alexyk has quit [Read error: Connection reset by peer]

03:30 philtor has joined #ocaml

03:31 AxleLonghorn has left #ocaml []

03:32 Amorphous has joined #ocaml

03:33 alexyk has joined #ocaml

03:37 alexyk has quit [Read error: Connection reset by peer]

03:48 alexyk has joined #ocaml

04:05 alexyk has quit [Read error: Connection reset by peer]

04:24 alexyk has joined #ocaml

04:37 eye-scuzzy has quit [Remote host closed the connection]

04:37 eye-scuzzy has joined #ocaml

04:42 alexyk has quit [Read error: Connection reset by peer]

04:52 alexyk has joined #ocaml

05:05 alexyk has quit [Quit: alexyk]

05:38 ModusPwnens has joined #ocaml

05:38 <ModusPwnens> Hello. Can someone help me with...well I don't really know what it's called

05:38 <ModusPwnens> I'm working with .mly and .mll files

05:38 arubin has quit [Quit: arubin]

05:38 <ModusPwnens> it's for an assignment, but it wasn't really explained at all and I don't understand the syntax

05:39 <ModusPwnens> I've googled and found some documents but I am still confusewd.

05:39 <ModusPwnens> I'm creating my own lexicon and parser I think..

05:39 <ModusPwnens> Anyways, I've defined some tokens like <int> Num, and <string> Id

05:40 <ModusPwnens> and then the start variable is of type <Nano.exp> exp

05:40 <ModusPwnens> and when I try to define the rules for Id, it yells at me because it's not of type Nano.exp

05:41 <ModusPwnens> Anyways, I don't really understand this and I was hoping someone could explain it to me..

05:43 <mrvn> you need to ask your TA. Those types are something they defined.

06:06 ModusPwnens has quit [Ping timeout: 276 seconds]

06:13 ikaros has joined #ocaml

07:08 ikaros has quit [Quit: Leave the magic to Houdini]

07:23 ttamttam has joined #ocaml

07:25 tnguyen has joined #ocaml

07:41 ttamttam has quit [Remote host closed the connection]

07:41 philtor has quit [Ping timeout: 240 seconds]

07:41 edwin has joined #ocaml

07:59 ygrek has joined #ocaml

08:12 edwin has quit [Quit: Leaving.]

08:12 edwin has joined #ocaml

08:13 edwin has quit [Remote host closed the connection]

08:13 edwin has joined #ocaml

08:14 drunK has quit [Remote host closed the connection]

08:32 bacam has quit [Ping timeout: 276 seconds]

08:36 Snark has joined #ocaml

08:46 Associat0r has quit [Quit: Associat0r]

09:23 Yoric has joined #ocaml

09:43 tony_ has joined #ocaml

09:44 myu2 has joined #ocaml

10:41 bacam has joined #ocaml

11:01 Yoric has quit [Quit: Yoric]

11:22 cyanure has joined #ocaml

11:23 avsm1 has joined #ocaml

11:26 avsm3 has joined #ocaml

11:26 avsm1 has quit [Read error: Connection reset by peer]

11:36 ikaros has joined #ocaml

11:44 boscop has joined #ocaml

11:45 Obfuscate has quit [Ping timeout: 276 seconds]

11:47 Obfuscate has joined #ocaml

11:49 coucou747 has joined #ocaml

13:03 lopex has joined #ocaml

13:31 tony_ has quit [Ping timeout: 240 seconds]

13:43 RyanRN has joined #ocaml

14:01 avsm3 has quit [Quit: Leaving.]

14:02 Edward has joined #ocaml

14:06 tony_ has joined #ocaml

14:42 alexyk has joined #ocaml

14:43 alexyk has quit [Read error: Connection reset by peer]

14:55 harrisonpartch has joined #ocaml

14:59 avsm has joined #ocaml

15:08 alexyk has joined #ocaml

15:19 sepp2k has quit [Quit: Leaving.]

15:26 RyanRN has quit [Quit: Leaving.]

15:27 ulfdoz has quit [Quit: deprecated]

15:27 alexyk has quit [Read error: Connection reset by peer]

15:31 ulfdoz has joined #ocaml

15:38 tnguyen has quit [Remote host closed the connection]

15:40 alexyk has joined #ocaml

15:43 RyanRN has joined #ocaml

15:44 alexyk has quit [Client Quit]

15:50 alexyk has joined #ocaml

15:54 orbitz has quit [Ping timeout: 240 seconds]

15:54 alexyk has quit [Read error: Connection reset by peer]

16:00 orbitz has joined #ocaml

16:03 alexyk has joined #ocaml

16:04 alexyk has quit [Read error: Connection reset by peer]

16:11 Edward has quit [Ping timeout: 240 seconds]

16:14 alexyk has joined #ocaml

16:19 ftrvxmtrx has quit [Quit: Leaving]

16:19 alexyk has quit [Read error: Connection reset by peer]

16:22 ftrvxmtrx has joined #ocaml

16:28 alexyk has joined #ocaml

16:31 krktz has joined #ocaml

16:31 <krktz> hi

16:31 <krktz> i'm looking for a way to know if, during an integer addition/multiplication/division etc., a bit overflow happened

16:32 <krktz> I first thought I could check the sign of the result, but it doesn't work in all cases (in max_int * 3, both sides are positive and the result is too, but it's still wrong)

16:32 <flux> there are bit tricks for that

16:33 <flux> or, rather, good recipes for detecting such situations

16:33 <flux> I don't have a pointer, though, but perhaps google is your friend :)

16:33 <krktz> :)

16:33 <thelema> krktz: batteries has some code for doing this, iirc.

16:33 * thelema checks

16:34 <thelema> BatInt.Safe_int

16:35 op414 has joined #ocaml

16:36 <thelema> yup, here: https://github.com/ocaml-batteries-team/batteries-included/blob/master/src/batInt.ml#L119

16:38 alexyk has quit [Quit: alexyk]

17:13 alexyk has joined #ocaml

17:17 alexyk has quit [Read error: Connection reset by peer]

17:18 <thelema> We could definitely use a better check for multiplication overflow - division is expensive

17:20 <ygrek> http://gdsfh.dyndns.org/kamlo/InfixOperators

17:21 <thelema> that code only works for 32-bit ints

17:22 <ygrek> yup

17:22 <thelema> I don't think we can promote 63-bit ints to 128=bit for the multiply

17:22 <ygrek> :)

17:22 avsm has quit [Quit: Leaving.]

17:27 <flux> the last recipe from: http://www.fefe.de/intof.html

17:27 <flux> the principle should be portable

17:30 alexyk has joined #ocaml

17:31 <thelema> flux: yes, I guess that's a reasonable way to do it, except 63-bit ints add lots of annoying corner cases, I expect

17:33 alexyk has quit [Read error: Connection reset by peer]

17:35 tony_ has quit [Ping timeout: 276 seconds]

17:46 alexyk has joined #ocaml

17:49 alexyk has quit [Read error: Connection reset by peer]

18:03 arubin has joined #ocaml

18:38 rien has joined #ocaml

18:39 ymasory has joined #ocaml

19:13 Snark has quit [Quit: Ex-Chat]

19:23 alexyk has joined #ocaml

19:24 RyanRN has quit [Quit: Leaving.]

19:24 RyanRN has joined #ocaml

19:27 alexyk has quit [Read error: Connection reset by peer]

19:36 alexyk has joined #ocaml

19:38 alexyk has quit [Read error: Connection reset by peer]

19:50 alexyk has joined #ocaml

19:53 ttamttam has joined #ocaml

19:53 ttamttam has left #ocaml []

19:56 tony_ has joined #ocaml

19:58 alexyk has quit [Read error: Connection reset by peer]

20:04 alexyk has joined #ocaml

20:05 haelix_ is now known as haelix

20:07 harrisonpartch has quit [Ping timeout: 246 seconds]

20:08 alexyk has quit [Read error: Connection reset by peer]

20:12 hyperbor1ean has quit [Quit: leaving]

20:18 harrisonpartch has joined #ocaml

20:22 alexyk has joined #ocaml

20:22 harrisonpartch has quit [Client Quit]

20:24 alexyk has quit [Read error: Connection reset by peer]

20:31 philtor has joined #ocaml

20:32 <thelema> hmm, how to randomly generate two numbers that sum to more than max_int?

20:32 <thelema> (other than let a = rand in let b = max_int - a + 1)

20:33 alexyk has joined #ocaml

20:35 hyperboreean has joined #ocaml

20:38 alexyk has quit [Read error: Connection reset by peer]

20:47 alexyk has joined #ocaml

20:48 alexyk has quit [Read error: Connection reset by peer]

20:50 <mrvn> something like let t = max_int + rand in let a = rand in (a, t - a)

20:52 enthymeme has joined #ocaml

20:52 <thelema> well, I guess a = rand in b = max_int - a + rand works

20:54 ikaros_ has joined #ocaml

20:55 <mrvn> that could overfow leaving you with something which sum is quite small.

20:55 <thelema> isn't it identical to yours?

20:55 <mrvn> t is ment to be int64

20:56 <flux> making even a random integer that is 0..max_int is quite difficult..

20:56 <thelema> my native ints are int64

20:56 <thelema> well, .int63

20:56 <mrvn> thelema: that extra bit is important :)

20:56 <thelema> flux: huh? no it's not - the code is in batteries

20:56 <flux> or atleast non-obvious. I think I should file a bug at some day :)

20:56 <flux> (or find an existing one)

20:56 <thelema> I wrote it, it took me 5 minutes

20:56 <mrvn> flux: huh? Make a int64 one can call to_int

20:57 <mrvn> s/can/and/

20:57 <thelema> mrvn: heh, that's even easier than what I wrote

20:57 <thelema> although mine can algo generate random numbers

20:57 <thelema> s/random/negative/

20:57 ikaros has quit [Ping timeout: 272 seconds]

20:58 <flux> so Int64.to_int (Random.int64 (Int64.of_int max_int)) it is, great..

20:58 <mrvn> + abs() if you want positive

20:58 alexyk has joined #ocaml

20:59 <flux> but, off to sleep

20:59 * thelema is just loring and shifting

21:01 philtor has quit [Ping timeout: 240 seconds]

21:02 alexyk has quit [Client Quit]

21:06 avsm has joined #ocaml

21:15 myu2 has quit [Remote host closed the connection]

21:24 ulfdoz has quit [Ping timeout: 276 seconds]

21:25 alexyk has joined #ocaml

21:26 alexyk has quit [Client Quit]

21:31 alexyk has joined #ocaml

21:42 alexyk has quit [Read error: Connection reset by peer]

21:49 tony_ has quit [Quit: Ex-Chat]

22:01 munga has joined #ocaml

22:02 myu2 has joined #ocaml

22:02 alexyk has joined #ocaml

22:03 edwin has quit [Remote host closed the connection]

22:07 alexyk has quit [Client Quit]

22:11 fraggle_ has quit [Quit: -ENOBRAIN]

22:13 mnabil has joined #ocaml

22:18 avsm has quit [Quit: Leaving.]

22:18 ikaros_ has quit [Quit: Leave the magic to Houdini]

22:18 fraggle_ has joined #ocaml

22:25 tony_ has joined #ocaml

22:28 munga has quit [Ping timeout: 276 seconds]

22:35 cyanure has quit [Ping timeout: 250 seconds]

22:36 BiDOrD_ has joined #ocaml

22:38 BiDOrD has quit [Ping timeout: 240 seconds]

22:55 philtor has joined #ocaml

22:56 ygrek has quit [Ping timeout: 240 seconds]

23:07 boscop has quit [Ping timeout: 240 seconds]

23:08 kig has quit [Read error: Operation timed out]

23:08 Tobu has joined #ocaml

23:09 Fullma has quit [Quit: Fullma]

23:12 kig has joined #ocaml

23:27 philtor has quit [Ping timeout: 240 seconds]

23:58 enthymeme has quit [Ping timeout: 260 seconds]