April 2011 - pro - mailman3.common-lisp.net

[pro] Lisp for High Performance Transaction Processing is private
by Yakov Zaytsev 27 Apr '11

27 Apr '11

Hello, all Scott gave me a hint in previous topic and I've came across this interesting video by Daniel while googling. http://www.youtube.com/watch?v=xquJvmHF3S8 There are many links to it on the Internet, but it's marked as "private" now. I was disappointed :-( Do anybody have a copy or can give a hint how to watch the talk?

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[pro] multiple Lisp images
by Yakov Zaytsev 27 Apr '11

27 Apr '11

Hello, all I again have a scenario as follows. Say, you have an enterprise-y or CAD-y application. From one side, you extend it in Lisp. Be it a plugin (i.e. LISPWORKS:DELIVER with :DLL-EXPORTS) or standalone Lisp process which communicates with the application via some provided SDK APIs; these two cases do not actually differ for us. >From the other side, you have your own fat Lisp application which you want to communicate with the plugin. Example: NPAPI plugin provides data for later processing by big Lisp. Here is a problem arises. How to pass sexps as transparently between the two Lisps as possible? Yeah, I programmed in Erlang for some time. Basically, I want that kind of "transparency", though I don't thing that it definitely must be message passing between quasi-processes.. There are might be some variations but I guess you got the idea

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Re: [pro] lisp scientific computing libraries
by A.J. Rossini 19 Apr '11

19 Apr '11

My N-bits on the subject (speaking as an amateur maintainer and occassional developer of lisp-matrix, and doing a bit of non-lisp numerics/informatics/computation professionally): I'd probably go with GSLL if you need to "get the job done" , it has a range of numerical domains implemented (but requires GSL, algorithms/implementations are reasonable but not always world-class). Matlisp works, is stable, but needs a bit of cleanup/refinement/refactoring, and requires Lapack and a few other Fortran libraries, and uses it's own FFI approach for Fortran. I wish it had a Fortran-front end for CFFI implemented. But "it works". linear-algebra (on github, and see recent posts) looks like a clean package, lisp-only, and so far I like it very much, but havn't had as much experience with it as I have with the other 3 you mention, so havn't had time to suss-out any issues. I don't recall if it has quad-programming, if not you'd have to add on the quad-programming algorithm, but that isn't too hard (i.e. following a journal article, for an undefined "hard"). You could also go via R, through RCL (works well) or RCLG (which I maintain), and the quad programming packages for that system. Highly recommend R as a non-lisp system for scientific computing. It's only fault is that it isn't common lisp. Lisp-matrix is a work in progress. As much as I'm fond of it, I have a hard time recommending it. best, -tony On Mon, Apr 18, 2011 at 10:38 PM, R. Matthew Emerson <rme(a)clozure.com> wrote: > What's the state of scientific computing libraries in CL? > > There appear to be numerous projects that address this particular area > at different levels: > > * GSLL: http://common-lisp.net/project/gsll/ > * Matlisp: http://matlisp.sourceforge.net/ > * lisp-matrix: http://common-lisp.net/project/lisp-matrix/ > > and certainly more. > > If anyone on the list works in this area, I'd be interested to hear > about what libraries you are using. If you'd care to share any pros and > cons, that would also be appreciated. > > (As a bit of an aside, I will mention that one particular area of > interest is quadratic programming. > > The package at http://sigpromu.org/quadprog/ package looked interesting, > but it doesn't come with source any more, and is meant to work with > Matlab. > > If by some chance someone is familiar with this area, perhaps you could > offer some recommendations? > > Pretty much anything with a C header file would be pretty easy to use.) > > _______________________________________________ > pro mailing list > pro(a)common-lisp.net > http://common-lisp.net/cgi-bin/mailman/listinfo/pro > -- best, -tony blindglobe(a)gmail.com Muttenz, Switzerland. "Commit early,commit often, and commit in a repository from which we can easily roll-back your mistakes" (AJR, 4Jan05). Drink Coffee: Do stupid things faster with more energy!

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[pro] Compiler APIs in Common Lisp
by Matthew Swank 13 Apr '11

13 Apr '11

I am current reading an interesting paper on Racket's macro system (referenced here: http://lambda-the-ultimate.org/node/4196 ), and some of the objects they expose quack like CLTL-2 Environments: http://www.cs.cmu.edu/Groups/AI/html/cltl/clm/node102.html. I have read that having write access to environments makes it hard for the compiler to optimize code. However, even portable read only access would be helpful. Does anyone besides me and Cyrus Harmon (http://cyrusharmon.org/blog/display?id=113) miss Environments? Matt

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[pro] code organization and name conflicts
by Ryan Davis 13 Apr '11

13 Apr '11

When working on a larger lisp code base, one with 10+ files in one package, I begin to get nervous about accidental name conflicts, and was wondering how other people deal with this. Here's the scenario I'm worried about: * dsl.lisp, written by a coworker two years ago, has a number of small functions that are helpers for the main #'WRITE-DSL-REPORT function; one of these helpers is #'GET-WAN-IPS * nagios-config.lisp, written by me today, has a number of small functions that are helpers for the main #'WRITE-NAGIOS-CONFIG function; one of these helpers is #'GET-WAN-IPS * I miss the compiler warning about redefining #'GET-WAN-IPS * I test my code, it works in my REPL so I commit and call it a day * Code eventually gets pushed to production and #'WRITE-DSL-REPORT is broken It doesn't happen very often (and testing procedures usually catch stuff before it goes to production), but it seems like there should be a nicer way to deal with helper functions that you want to develop/test from the REPL, but don't need to be used outside the current file. I had a few ideas to solve it, none of which I really like. I could add a top-level FLET for the file, but the extra indentation will be annoying and it'll be harder to test/maintain those helper functions. I could define a helper package, per-file, and put my helper functions in that package (e.g. (defun nagios-config-helpers::get-wan-ips ...)), but that feels funny and awkward, which usually means it's a bad idea. I could break up my code into many smaller packages, each exporting and importing the functions needed elsewhere in the system, but that seems like recipe for dependency headaches and a lot of unneeded paperwork. Do other people have this anxiety? Are there elegant ways to deal with it? (besides medication and more unit testing) Thanks, -- Ryan Davis Acceleration.net Director of Programming Services 2831 NW 41st street, suite B Gainesville, FL 32606 Office: 352-335-6500 x 124 Fax: 352-335-6506

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[pro] PDM Review
by aashish atl 13 Apr '11

13 Apr '11

Hi, I am developer of aspiwork-pdm project that I moved to cl.net in Feb'11. Motivation for this project can be found on its devel mailing list. At present, application is a crude expression of what I intended to do. I spoke to some prospects in my locality. Most of the office owners agree that integration of their resources would be a great idea. Yet I am not sure if their hesitation purely relates to technical issues... I am not getting a satisfactory feedback. With this much, I have virtually not touched the code for weeks. I welcome your perspectives on this project. While comments on its actual code may suit project's own mailing list; here I seek some enlightenment on project's concept/design, utility in day to day scenario, acceptance of common lisp for such application... any other comment from your point of view. I see document management and process flow modules in a few 'cloud' services and upscale ERP installation. I am wondering if these are practical at smaller level with common lisp as a tool. I guess few of you must have implemented similar systems. Thanks. Regards -Aashish

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[pro] Order of package declarations
by Daniel Weinreb 06 Apr '11

06 Apr '11

In large Lisp systems, it's easy to run into problems with the order in which files are loaded and compiled. One often-vexing issue is where to put package declarations. If a file names an exported symbol such as foo:bar, the package foo with its export list must have been loaded earlier. In general, it seems to me that in a big complicated system with lots of packages, it would be great if you could just first load all the files with defpackage forms, and get all those packages created and all the external variables externalized, and then load everything else. However, in a situation I'm working on now, that doesn't work, because package X has (:import-from :y :a1 :a2), and the symbols :a1 and :a2 are not exported from :y. That is, X is exporting internal symbols of Y. This fails, because the symbols :a1 and :a2 do not exist, because they get created only when the files that define them get loaded. So doing all the package declarations first does not work. Possible approaches: (1) Too bad; you really do have to load the Lisp files that created those internal symbols after defining package X and before defining package Y. (2) For Y to export symbols of X that X does not export, while being valid Common Lisp, is a bad practice. It's a little hard to explain why we're doing this at all. I think it is historical. Originally there was only package X. Then it was considered a good idea to classify some of the functions in package X under a new package name, Y, to make the rest of the code clearer. Unfortunately, the symbols and functions and macros of package X may be too entangled to separate them out the way we would have done had the partition between X and Y been done from the beginning. By "too hard" I mean that it's not worth the trouble to attain the goal, which was to remove a single ugly use of "::". But I'm interested in the topic anyway. -- Dan

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