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0:33:27
edgar-rft
Common Lisp is full of overloaded functions, you don't need to be afraid to add your own :-)
0:40:18
aeth
gabbiel: You have other options, e.g. https://github.com/markcox80/specialization-store/ but that will come at a performance cost without type declarations
0:43:12
gabbiel
aeth: yeah I was thinking, if symbols weren't restricted to one function, one could define many functions for a symbol, but that'd require declaration of types like in methods
0:44:45
aeth
well, no, if the library is robust enough, then you'd get runtime dispatch or compile-time dispatch, but the compile-time dispatch would be (1) only on certain implementations that have the proper extensions and (2) only if you have type declarations in your code because the type inference isn't exposed even to the extensions from point #1
0:51:00
aeth
gabbiel: Yes, I was talking about in the caller, not in the definition. The definition would need types.
0:52:32
aeth
gabbiel: And there's nothing (other than pulling in yet another dependency) stopping a defun wrapper from using something like defspecialization as a backend when requested.
3:27:46
asarch
One very very very stupid question: If I compile the newest release of SBCL (1.5.5) with an old version (1.4.8) will this resulting binary differ from the one compiled with the newest release (1.5.5 with the resulting binary from 1.4.8)?
3:30:18
beach
asarch: The result ought to be the same. If it is not, then that might indicate a problem.
3:35:49
asarch
cmp ./src/runtime/sbcl $( which sbcl ): ./src/runtime/sbcl /usr/local/bin/sbcl differ: char 307242, line 681
3:51:46
akoana
asarch: beach is right, the sbcl binary contains a build timestamp like hostname-user-yyyy-mm-dd-HH-MM-SS
3:52:42
akoana
asarch: may be you can see it with grep -a -o -w yourhostname....................... ./src/runtime/sbcl
4:07:13
akoana
ACTION suspects that could be done in a few lines of Common Lisp, display n bytes of both files starting from the difference
4:07:19
asarch
OpenBSD's cmp doesn't support the -b flag, however, this its output (every ; represents a newline): 307242 61 62; 307244 60 61; 307248 62 70
4:08:22
asarch
$( which sbcl ): /usr/local/bin/sbcl <- This was the 1.5.5 compiled with the old 1.4.8 version without '--fancy'
6:10:02
akoana
beach: now I've done a quick and dirty (and bad style but working) cmp replacement in Common Lisp :)
6:18:22
edgar-rft
I think we did a little mistake. The sbcl binay is only the loader, while the Lisp image on my machine is stored under /usr/lib/sbcl/sbcl.core. IMO it would make much more sense to cmp(1) the Lisp images instead of the loader.
6:53:35
akoana
edgar-rft: good point, seems sbcl-core also has that build timestamp, beginning at byte 32
7:02:31
akoana
edgar-rft: the cmp will get tricky if you compare identical versions compiled at different times, how to ignore false positives only differing in some build info...
7:12:26
edgar-rft
akoana: I'd just simply count the number of different bytes. If they're more than say 10% of the whole binary size then there's something fishy. If they're only a few then it's probably because of timestamps and similar things that can be ignored. In case of doubt I'd ask on #sbcl.
7:18:09
edgar-rft
If you really want you could use a hex editor (or Emacs hexl-mode) to look at the context where the different bytes occur.
7:20:26
akoana
edgar-rft: oh, didn'nt know hexl-mode, does it handle big files well? (fearing my emacs to suck up all my memory)
7:25:52
edgar-rft
akoana: I just tired it, Emacs loads a 47M file without problems, after M-x hexl-mode it took appox 15 seconds to convert the binary mess into a scrollable hexdump, Emacs needed appox 100MB RAM for that.
7:28:03
akoana
edgar-rft: thank you for sharing and trying so now I'm ready to dare to use hexl-mode :)
7:31:42
edgar-rft
akoana: there are also hexdump tools for the command-line that don't load the whole file in one piece, but I don't know their name or their usage off-head right now.
7:33:25
akoana
edgar-rft: yes, on linux I'm using xxd, hexdumü or od for that - they can easily handle GB sized files
7:39:50
edgar-rft
hexidi? I only know Heidi, the little girl, who lived with her grandpa in the mountains
7:50:29
scymtym
akoana: for printing hexdumps in cl, there is https://github.com/scymtym/utilities.binary-dump
7:54:34
akoana
we are on the hexdump trail since asarch asked how to compare sbcl binaries hours ago - lol