another frustrating learner question, CLOS
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From: Pascal J. Bourguignon on 26 Feb 2010 08:26 piscesboy <oraclmaster(a)gmail.com> writes: > I don't think so. The hyperspec is the collection of documents that is > supposed to come up when you type (describe 'symbol-name) right? Wrong. What's wrong with the youngs today? The world wide web has existed for THIRTY YEARS now! What do they learn in school? Use google! Type hyperspec and find this: http://www.lispworks.com/documentation/HyperSpec/Front > All that does is bring up a URL that I have to cut and paste onto a > web browser. I assume you're using clisp, which indeed links describe to the web. You get this partial behavior because your clisp is ill configured. There are two variables you need to chek: CUSTOM:*BROWSERS* which is an a-list mapping keywords to a list containing a command and arguments to run a web browser on an url. CUSTOM:*BROWSER* which is one of the keywords mentionned in CUSTOM:*BROWSERS*. You can set CUSTOM:*BROWSER* (and CUSTOM:*BROWSERS* if you don't like the default value) in your ~/.clisprc file. Here is what I have: (setf CUSTOM:*BROWSER* :emacs-w3m CUSTOM:*BROWSERS* '((:firefox "firefox" "~A") (:NETSCAPE "netscape" "~A") (:NETSCAPE-REMOTE "netscape" "-remote" "openURL(~A,new-window)") (:MOZILLA "/usr/local/apps/mozilla-1.7/mozilla" "~A") (:MOZILLA-REMOTE "/usr/local/apps/mozilla-1.7/mozilla" "-remote" "openURL(~A,new-window)") (:KONQUEROR "kfmclient" "openURL" "~A") (:LYNX "lynx" "~A") (:LYNX-XTERM "xterm" "-e" "lynx" "~A") (:LINKS "links" "~A") (:LINKS-XTERM "xterm" "-e" "links" "~A") (:W3M "w3m" "~A") (:W3M-XTERM "xterm" "-e" "w3m" "~A") (:MMM "mmm" "-external" "~A") (:MOSAIC "xmosaic" "~A") (:EMACS-W3 "emacsclient" "-n" "-e" "(w3-fetch \"~A\")") (:EMACS-W3M "emacsclient" "-n" "-e" "(w3m-browse-url \"~A\")") (:openstep "open" "~A")) > I've been programming Lisp for only a little over two months, so how > do I find out if it is installed locally? And then install it? The HyperSpec is the reference, the standard defining Common Lisp. It's rather arid, but once you know how to use it, it's great. URL above. In addition to the language, you need to know your implementation and its variations and extensions. For this, you need to read its manual. In the case of clisp, it's the Implementation Notes found at http://clisp.cons.org/impnotes/ Depending on the system and distribution you use, there may be a package management system that would install both correctly automatically for you. Otherwise, you need to know how to use your system, and how to install software on it. -- __Pascal Bourguignon__
From: Giovanni Gigante on 26 Feb 2010 09:33 piscesboy wrote: > I don't think so. The hyperspec is the collection of documents that is > supposed to come up when you type (describe 'symbol-name) right? All > that does is bring up a URL that I have to cut and paste onto a web > browser. > > I've been programming Lisp for only a little over two months, so how > do I find out if it is installed locally? And then install it? 1. FYI, the hyperspec is a hypertext documenting the ANSI Common Lisp standard: http://www.lispworks.com/documentation/HyperSpec/Front/index.htm 2. download it in archived form from here: ftp://ftp.lispworks.com/pub/software_tools/reference/HyperSpec-7-0.tar.gz 3. unpack it somewhere on your computer 4. edit your .emacs and add something like: (setq common-lisp-hyperspec-root "file:///where/you/unpacked/your/Hyperspec/") 5. restart emacs and slime 6. in slime, move over a symbol and try: C-c C-d h 7. enjoy.
From: ccc31807 on 26 Feb 2010 09:47 On Feb 26, 2:45 am, Tamas K Papp <tkp...(a)gmail.com> wrote: > Most people who learned CL did it because it was enjoyable. Sure, > there are some initial hurdles, and all encounter minor frustrations > in the learning process. I am quite surprised that for you, it feels > like "pulling teeth, except more painful". I have never experienced > that when learning CL --- quite the opposite. 'Pulling teeth' refers to the process, not the technology. My point was that extra-language problems, like a corrupted environment, can be quite painful. I've learned a number of languages, both on my own and in academic settings, and had the privilege of teaching a couple of languages in an academic setting. In a brace delimited language, like C or Perl, an error like substitution a '}' for a ')', or vice versa, won't necessarily throw a syntax error, but it will produce weird logic errors. If you have made this kind of error several times, you begin to recognize the pattern and check your delimiters. You can't expect a student to have this kind of experience. I have been dealing with 'premature end of script headers' errors in Apache applications for more than ten years, and have gotten adept at fixing these kinds of problems. Last week, I moved a CGI app from a Windows server to a Linux server, and got this error, which absolutely mystified me ... painful like pulling teeth. After a couple of hours, I discovered the dos2unix command, which fixed the error. Afterwards, talking to someone about this, he asked me, first thing, if I had tried the dos2unix command. This is the benefit of experience. It's not Lisp that's painful, is the process of learning without a guide that can grease the skids and alert the learner to the idiosyncratic quirks of a language that a newbie can't anticipate. CC.
From: ccc31807 on 26 Feb 2010 10:10 On Feb 25, 6:08 pm, Ron Garret <rNOSPA...(a)flownet.com> wrote: > That rumbling sound you hear is Erik Naggum rolling over in his grave. > > http://groups.google.com/group/comp.lang.lisp/msg/fc76ebab1cb2f863 > > rg <quote> you can commit any dirty hack in a few minutes in perl, but you can't write an elegant, maintainabale program that becomes an asset to both you and your employer; you can make something work, but you can't really figure out its complete set of failure modes and conditions of failure. </quote> What if committing the dirty hack is the solution to the problem? Like processing a data file in a one time script? Why spend an hour writing an elegant, maintainable program when all you need is a one liner that you will never need again? True, the one liner will be ugly, obtuse, unreadable, unmaintainable, but if it does the job quickly and easily, why use something that is hard and slow? <quote> I'll concede, however, that it is very important to be able to understand what perl programmers do. if you don't understand what they are talking about, you won't understand what they are actually trying to accomplish with all the incredibly braindamaged uses of hash tables and syntactic sadomasochism, and you won't be able to see through their charades and "just one more hack, and I'll be there" lies. </quote> If you need a puree, you run the food through the food processor, and the incredibly brain damaged hash tables and syntactic sadomasochism is simply the form of the processor. I'll agree in a heartbeat that a block of Perl code can look like line noise, particularly if it involves regular expressions and hash references (which it usually does), but Perl's facility of (1) providing a powerful tool for pattern recognition, matching, and replacement, and (2) providing sophisticated and very finely grained data structures makes life easy WHEN THE USE OF THESE TOOLS IS APPROPRIATE TO THE JOB! CC.
From: Tamas K Papp on 26 Feb 2010 10:18
On Fri, 26 Feb 2010 06:47:44 -0800, ccc31807 wrote: > On Feb 26, 2:45 am, Tamas K Papp <tkp...(a)gmail.com> wrote: >> Most people who learned CL did it because it was enjoyable. Sure, >> there are some initial hurdles, and all encounter minor frustrations in >> the learning process. I am quite surprised that for you, it feels like >> "pulling teeth, except more painful". I have never experienced that >> when learning CL --- quite the opposite. > > 'Pulling teeth' refers to the process, not the technology. My point was > that extra-language problems, like a corrupted environment, can be quite > painful. There is nothing in your post to indicate that your environment was corrupted in any way. Occam's razor suggests "confused user" instead of "corrupted environment". > I've learned a number of languages, both on my own and in academic > settings, and had the privilege of teaching a couple of languages in an > academic setting. In a brace delimited language, like C or Perl, an You have been asking questions here about Lisp for about half a year, you got this far with learning it, and you have been teaching people programming? I am lost for words. > It's not Lisp that's painful, is the process of learning without a guide > that can grease the skids and alert the learner to the idiosyncratic > quirks of a language that a newbie can't anticipate. Lisp is the most coherent language I know of. It has a few quirks, but it fits together quite well. There are plenty of good guides, many of them are free. PCL is an example. Given the array of excellent Lisp books, Lisp tutorials, and other resources, complaining about the lack of a "guide" is ... (no, I don't want to complete the sentence). Tamas |