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11:43:31
jackdaniel
complex float operations improvements in ECL: http://hellsgate.pl/files/2542707e-report.html (no optimizations in compiler yet whatsoever, just generic dispatch on math operations). still behind sbcl though :c
11:44:28
jackdaniel
mandelbrot/dfloat is put there for scale, we should do much better job with double floats too
13:29:51
jackdaniel
I've put results in clim app: https://imgur.com/drAprZJ.png (numbers are little different - I've run it again and removed dfloat)
13:55:51
mgsk
I have some dir `./src/contribs` that contains things like plugins that depend on the main library. I want these to be loaded whenever the main library is loaded. Is this something that ASDF can deal with?
13:56:40
mgsk
I guess just doing `(:file ...)` would suffice in that case. I was expecting something more complicated
13:57:13
mgsk
e.g. I don't know ahead of time what is in the contribs dir, so I can't write out all the appropriate `(:file ...)`forms.
13:58:07
jackdaniel
a few months back I wrote an "autodiscovery" module class for someone, link should be somewhere in logs
21:07:37
vms14
I have no idea how to convert a string to a list of symbols, I just take the first element
21:09:48
aeth
vms14: So the problem is that you're reading in a line into a string, and you're turning "Hello world" into |Hello world| instead of (HELLO WORLD)
21:11:17
vms14
I'm trying to parse input, I just want read every symbol from the input until the user press enter
21:13:37
aeth
vms14: One thing you could do, and it's quite a hack, is (read-from-string (read-line))
21:13:53
vms14
the thing is usually I won't know how many symbols will be, and the delimiter is the newline
21:14:04
aeth
vms14: the second value in read-from-string is where it left off so you can loop on that second value
21:14:25
pjb
vms14: or: (loop for element = (extract-one-item (read-line)) until (eof-element-p element) collect element)
21:15:03
pjb
vms14: using READ or READ-FROM-STRING, you allow input to do whatver it wants with your lisp image, by default.
21:15:11
aeth
vms14: (read-from-string (read-line)) for a line "hello world" will return (values HELLO 5)
21:16:30
aeth
vms14: you can then do (read-from-string (read-line) nil nil :start 5) to get (values WORLD 11)
21:16:53
pjb
So you would want to bind *read-eval* to NIL. but other reader macros can be problematic: (read-from-string "#8931289312839012*") for example, could DOS your system by trying to allocate all its RAM. (or just signal a condition, depending on the implementation).
21:17:19
pjb
another thing is that reading symbols will intern them, so if there's a loop, the input could fill your memory with useless symbols.
21:17:47
pjb
So you might want to intern the symbols in a throw away package that you can delete-package when you're done.
21:17:47
aeth
vms14: The "correct" (safe) way to do things is to parse the string, perhaps with cl-ppcre
21:18:15
aeth
By the time you add in the validation pjb is talking about, the parse solution probably becomes more concise than the elegant solution that pjb and I both said simultaneously
21:18:57
pjb
vms14: (split-sequence #\space (read-line) :remove-empty-subseqs t) is usually all you need.
21:19:36
aeth
Which to use is debatable. split-sequence is a smaller dependency, but if you're doing additional parsing, you might be using cl-ppcre anyway
21:19:40
pjb
(ql:quickload :split-sequence) (use-package :split-sequence) (with-input-from-string (*standard-input* "Hello world! How do you do?") (split-sequence #\space (read-line) :remove-empty-subseqs t)) #| --> ("Hello" "world!" "How" "do" "you" "do?") ; 27 |#
21:21:23
aeth
If you wanted "absolutely 0" overhead, you can get that. Well, not quite 0, you'd have to track start and end positions for each substring. String/sequence functions take in start and end so you can just work like that.
21:22:50
pjb
(com.informatimago.common-lisp.cesarum.array:positions #\space "Hello world! How do you do?") #| --> (5 12 16 19 23) |#
21:24:58
pjb
(let ((string "Hello world! How do you do?")) (loop :for start := 0 :then (1+ end) :for end :in (com.informatimago.common-lisp.cesarum.array:positions #\space string) :collect (cons start end) :into result :finally (return (nconc result (list (cons end (length string))))))) #| --> ((0 . 5) (6 . 12) (13 . 16) (17 . 19) (20 . 23) (23 . 27)) |#
21:25:07
aeth
You could store positions in an array with the :element-type alexandria:array-index, which will probably round up to fixnum or "unsigned fixnum" (it will show up as some strange looking unsigned-byte size like (unsigned-byte 62)) or (in 64-bit implementations) (unsigned-byte 64)
21:25:43
pjb
And then you can use (foo string :start (car pos) :end (cdr pos)) with most sequence functions to process the substrings. Or (subseq string (car pos) (cdr pos)) when you need to extract it.