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5:38:50
GoldRin
Bah, simple question, just having trouble with syntax. How would I apply an initial expression to an arugment within an flet in common lisp.
5:40:52
GoldRin
Basically just this: (let dup ([i 0]) ... I just don't know how I would translate from scheme to CL.
5:41:53
loke
I thought Scheme used the same syntax for LET as Common Lisp, but that's not a notation I'm familiar with.
5:42:33
GoldRin
local binding for a function named "dup" with the argument i which is initialised to 0 and local to "dup"
5:44:20
GoldRin
(I suck at IRC, so I hope this works) loke: I've found that scheme and CL have slightly different ordering of parenthesis and it just has been throwing me off.
5:45:46
d4ryus
GoldRin: if you want to call dup from within dup, you have to use labels. labels/flet is like let*/let respectively
5:51:18
GoldRin
Alright, I think I need to do some more reading and research then. This isn't anything really important at least.
5:51:50
pjb
(let dup ((d '()) (e l)) (if (null? e) d (dup (cons (car e) (cons (car e) d)) (cdr e)))) would be written: (loop :named dup :for x :in e :collect x :collect x)
5:52:37
beach
GoldRin: The Common Lisp standard does not require tail-call optimization, so you can't rely on that. Plus, tail-recursive functions are often less readable form of iteration.
5:53:49
loke
GoldRin: Also remembe rthat you really shouldn't do looping with recursion in Common Lisp. Instead, CL has a very strng LOOP construct that should be used.
5:55:22
beach
loke: You are right when it comes to linear structures. But it is common for tree-like structures.
5:58:09
beach
GoldRin: Scheme and Common Lisp are very different languages, especially when it comes to what is considered idiomatic code. It is preferable not to have a "Scheme accent" when you "speak Common Lisp".
6:01:33
beach
I am willing to bet that object-oriented programming is used a lot more in Common Lisp than in Scheme. I may be wrong about that, of course.
6:02:22
GoldRin
Well I'm not highly familiar with either, just I had studied scheme for a bit before studying common lisp. Thanks for all the info btw
6:04:48
loke
GoldRin: Common Lisp is a multiparadigm language, while Scheme is more of a "true" functional language (if there is such a thing)
6:05:20
pjb
beach: of course, 1- CL has a standard object system. 2- CL has the best object system of the world. :-)
6:08:51
GoldRin
I hadn't been using CLOS specifically, but when I reached the functional programming part of the CL book I'm going through, I guess I just assumed that scheme ideas would just translate over.
6:11:17
pjb
GoldRin: the only thing that doesn't translates well in CL from scheme, are generalized continuations. Delimited continuations are ok.
6:12:16
GoldRin
Yeah, I've heard about that. I never really got too far with continuations when I was studying scheme, but I'll probably go back once I've finished this book.
11:24:05
Godel[m]
When managing quicklisp with roswell, is it expected to symlink the project directory to local-project directory both in `~/.roswell/local-projects` and `~/.roswell/lisp/quicklisp/local-projects` ? That is the only way I can see to load the project via quicklisp in both slime and ros-repl.
11:26:07
no-defun-allowed
I usually symlink stuff into ~/quicklisp/local-projects to get them recognised by Quicklisp, and it does seem intentional given the pathname and that there's a function QL:REGISTER-LOCAL-PROJECTS so I'd guess so.
11:29:08
jackdaniel
Godel[m]: I think you'll get more lucky by pasting question on roswell repository
11:31:09
Godel[m]
jackdaniel: I think I solved it. But now I'm having trouble with `~/.sbclrc` which doesn't load on startup anymore (once I installed quicklisp and sbcl via roswell).
11:32:43
flip214
How would I access an Oracle DB from sbcl? I know about PostModern etc., but the best choice for Oracle is CL-DBI? does CLSQL work?
11:33:47
no-defun-allowed
If it uses the SQL wire protocol (which IIRC is a standardised thing), probably.
11:33:51
jackdaniel
Godel[m]: I've tried roswell and I had a lot of problems like that (so the experiment lead to software rejection)
11:35:00
no-defun-allowed
I tried to work on refactoring some code in Roswell and it was very nasty. Maybe that is just how "contrib" code goes being a lower priority, but it doesn't make me think too nicely of Roswell as a whole.
11:35:49
no-defun-allowed
And I basically spend all my CL work time in git or SLIME so I don't see why I want a Unix-y interface to CL system management either.
11:35:52
flip214
no-defun-allowed: what is an "SQL wire protocol"? every database has it's own (binary) protocol. I don't know about something like TELNET for SQL.
11:36:19
no-defun-allowed
Oh, maybe it isn't a standardised thing. I assumed every database used the same protocol.
11:37:27
no-defun-allowed
In the output of (ql:system-apropos "oracle") I see "dbd-oracle" and "hu.dwim.rdbms.oracle" which look promising though.
11:40:58
aeth
I like the concept of Roswell, but the implementation is a very buggy C program that's hard to upgrade. Someone should make a similar tool that assumes that the host already has a Common Lisp installed, just not literally every Common Lisp ever. That would greatly simplify things imo.
11:43:08
aeth
no-defun-allowed: The point of Roswell, at least to me, is so you can test with CLs that are either newer than your Linux distro offers or that your Linux distro doesn't offer.
11:45:32
aeth
Last time I tried Roswell for testing literally everything, it works for me for everything except for MKCL (not provided... but apparently it's provided now) and clasp (takes forever to compile and then fails for me... they really need a clasp-bin)
11:46:26
no-defun-allowed
Now I don't remember which file I thought I could clean up. Happens every time.
11:47:07
aeth
The main downside to Roswell seems to be that I have to close my current emacs+slime and launch emacs specially through "ros use foo && ros emacs &" in the terminal. And then I have to put "ros use sbcl-bin &&" in front of every other command because ros will remember and use foo for everything, and might have issues with using foo over SBCL.
11:48:24
jackdaniel
another problem is that you couldn't plug it with your own builds of desired software
11:49:24
aeth
it seems to detect my ~/quicklisp/local-projects. Do you mean your own builds of the implementations?
11:50:39
aeth
I guess it also means you probably can only use the trial versions of allegro and lispworks there.
11:52:26
no-defun-allowed
Oh, here is the file that spooked me: https://github.com/roswell/roswell/blob/master/lisp/extend-quicklisp.lisp
11:54:32
no-defun-allowed
Most of the read-from-string madness could be fixed with a #+asdf, unless it's uncertain if it'll get loaded before or after ASDF and Quicklisp maybe.
11:57:22
no-defun-allowed
But again, I don't run a pragmatic get-work-done-now ~1000 star project for making Lisp more digestible for a shitstain of an OS, I am just an armchar critic. I'll stop whinging now.
12:41:11
no-defun-allowed
But I can't tell if all this is intentional because we don't know if it will be loaded before Quicklisp and/or ASDF (in which case: what is the purpose of loading it?) or if it is just because the author did not consider it (which would hopefully lead to someone pointing out it could be cleaned up, or someone complaining at least)
12:43:46
no-defun-allowed
And now this problem will ponder my dreams if I'm not lucky. Eh well, night.
13:04:17
jmercouris
any reason not to use subseq to trim a list down from '(0 1 2 3 4) to '(0 1 2 3)?
13:04:35
jmercouris
I have this feeling in the back of my head that there is some other function I am not thinking of
13:07:02
lieven
of course, the usual wisdom applies that if the list becomes big or this is a common operation, a list might not be the best datastructure for the job
13:12:38
jmercouris
I do however have another problem I am trying to think of, I want to avoid writing a conditional here
13:52:00
shka__
is there anything like INTEGER-LENGTH but for finding the first position of the least significant 1 bit?
15:14:05
pfdietz
The LOG... functions in CL are effectively "infinite" 2's complement, so that trick works.
15:38:08
pjb
Always use the most generic operators, so that your functions are generic functions that can be applied on more types. So when you change your data structures, you don't have to rewrite all your program!
15:38:49
pjb
(defun foo (x) (subseq x 0 (1- (length x)))) (mapcar 'foo '( (1 2 3) #(1 2 3) "123")) #| --> ((1 2) #(1 2) "12") |#
15:39:18
pjb
(defun foo (x) (butlast x 1)) (mapcar 'foo '( (1 2 3) #(1 2 3) "123")) #| ERROR: The value #(1 2 3) is not of the expected type list. |# DUH!
16:12:36
flip214
I'm using CL-STORE and override SERIALIZABLE-SLOTS to not include an open stream in a class' instances. Upon restoring I don't get the :INITFORM NIL, but an unbound slot.
16:13:18
flip214
I'm fairly sure that did give back the :INITFORM a few years back; does someone know about an intentional change in CL-STORE?
16:27:22
flip214
well, (CL-STORE:RESTORE ...) should use the initform for unbound (ie. not serialized) slots
16:31:10
Bike
according to the blame the default backend has not had different behavior for standard objects in the last twelve years, and it doesn't look like it does anything with initforms
16:33:34
Bike
general initforms are forms that may refer to a lexical environment, so they aren't really serializable