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Autogenerating TOC

 [1/3] from: sharriff::aina::med-iq::de at: 17-Nov-2000 8:52


Hi guys! If there was an award for the most clumsy or silly looking code , I would definately win. Im trying to code a function that would automatically generate a TOC of of files in a directory Main TOC: A B C D and so on and so forth and every alphabet is a link to a sublist HTML file that contains links to files starting with the alphabet displayed in the main TOC HTML file A --> link to a file, a.html that contains links to files that all start with a, example ahouse .html. aaa.html, asbc.html e.t.c B ->link to a file, b.html that contains links to files that all start with b, example boing .html. badcode.html, blooper.html e.t.c heres what Ive done so far ( simplified, Ive removed the HTML basic and other formatting tags) ; initialize containers toc-list: temp-block: file-list: sorted-files: file-dir: sub-list: make block! 0 ; initialize link bits link-begin: {<a href="} close-link: {">} end-link: {</a>} file-dir: read %./ sort file-dir ; creates a block of files as strings foreach file file-dir [ append file-list (to-string file) ] ; generates first char of every file and saves result to "toc-list" foreach file file-list [append toc-list first :file sort file-list ; appends the real file names to "toc-list" block append toc-list file ; writes the toclist [ foreach char toc-list [ write (append sub-list ((join (to-file :toc-list) ".html") ( I gave up eventually. I really dont know how to link the generated TOC link list with the separate HTML files containing links to files in the directory to files sorted per alphabet or number. Suprisingly, this works. (har! har! "Tim Allen" code) files: read %./ sort files foreach file files [ append temp-block (to-string file) ] foreach file files [write %toc.html file-dir (append file-dir "<p></p>" append file-dir (join (join (join (join link-begin file) close-link) file) (end-link)))] but I dont know how to connect both code snippets together, I know this code looks weird, If I can get the principles right Ill try to clean it up somehow. I hope theres someone out there that can point me in the right direction. Best regards and thanks list for the anticipated help Sharriff Aina med.iq information & quality in healthcare AG

 [2/3] from: brett:codeconscious at: 18-Nov-2000 2:35


Hi Sharriff!
> Im trying to code a function that would automatically > generate a TOC of of files in a directory
...
> and every alphabet is a link to a sublist HTML file that contains links to > files starting with the alphabet displayed in the main TOC HTML file
...
> but I dont know how to connect both code snippets together, I know this > code looks weird, If I can get the principles right Ill try to clean it
up
> somehow.
I want to put forward some ideas I use all the time with any programming I do. Here's a good one - clean it up first and the solution to making it work will probably become obvious. If it doesn't, you will at least have an idea of where to look. Structuring your code through functions can help tremendously. If you make each function responsible for one task and give it a meaningful name your program becomes so much more readable. One consequence of doing this is that you come up with alternative ways to structure your programs or other opportunites to make it better - the success feeds off itself. The obvious other benefit to this of course that you can parameterise your code so that it becomes useful in other situations. So right now, you have a script that is close to what you want but is hard to change and it doesn't quite work. You need to methodically go through and make it better. Doing this will very likely make it obvious to you how to make you code work whre it isn't now. [BTW, I discovered a fancy word for this last year - "refactoring". Somebody coined the term and related it to the Object Oriented field. Then people could write and sell books on it. Many programmers have been doing this as a matter of course for years. ....Oh well, I thought it was interesting.] So... 1) First Isolate a basic function of your script, put brackets around it, give it a function name and call it using the new function name from the part where you would have cut it out from. Looking at your code maybe one such function could be GET-TOC-LIST. 2) Look through this function and try to define as many of the variables that you find as local. 3) Then identify the parameter variables. 4) The other variable are likely to be globals - can they be economically passed in as parameters using another form (object?) or should you redefine your function a bit?. Or maybe they just want to be global. Make sure your call to your function reflects your new parameter variables (or refinements). So now the function might be GET-TOC-LIST: function [directory Directory to process ][... 5) Repeat for more functions Maybe another function is MAKE-TOC-HTML toc-list (that will return a string of html code) Think now of the consequences of your function choices. I choose GET-TOC-LIST with a parameter of a directory to process. Great! This allows me to do the same thing for lots of directories. What about if I changed the definition of the function a little and added a parameter first-filename-character. With this I could process all the files in a directory that start with the letter "X" any time I liked (eg. after I know I just added a XANADU file). Another general point I'd like to make is that mixing in two different types of stuff together can be confusing. In this case an algorithm for generating information from directories, and HTML. My suggestion of a function MAKE-TOC-HTML confines the HTML stuff to one part of the script which clears the fog around the algorithm parts of the script. Other ways to do this might be to use objects or other scripts. After doing this you might decide that some of the original script just doesn't fit the new scheme of things. What is it there for? Does it work? Is it redundant? How can I get rid of it or legitimise it in the new script? As you gain experience with this sort of thing you end up visualising the consequences of choosing particular function tasks and parameters over other alternatives. Also, this process may stimulate ideas for radically different alternatives in approaching the problem. Ok, adding a second parameter that is a character seems good but this has implications of how toc-list is stored and how MAKE-TOC-HTML would work. This brings us to structuring of the data. Ok a change of voice - my thoughts on the problem as I write. How will toc-list hold its information? In your solution you have used multiple container to deal with this. You also have read the directory again - not a sin - but hey you've read it once already, you should be able to collect a lot of the info you need this first time. Here are some alternatives. 1) toc-list hold all the files for one character as a block Well this is straight forward, but it probably means I need a second parameter to MAKE-TOC-HTML to tell that function what to put in as a heading. 2) toc-list holds all the first-characters and the related files in some sort of block structure This is more complex, but I don't need to have the second parameter to MAKE-TOC-HTML because all the information is already in the block. But it means that MAKE-TOC-HTML will generate multiple files - oh oh what I am going to call them? Should the decision about what to call them reside inside MAKE-TOC-HTML? I'm not really happy yet. Meditating on my disquiet about how much these functions know about the overall task of making TOCs reminds me that the objective was a main table-of-contents pointing to other table-of-contents that finally point to the files. MAKE-TOC-HTML could be able to produce both of these types of files. All it needs is the relevent information. What is relevent to MAKE-TOC-HTML - surely just a heading and a pile of link information! Ok putting together some of the bits I've mentioned I come up with this combo toc-script might be structured like [ "A" [%apples.html %asparagus.html %almond.html] "C" [%carrots.html %candy.html %cute.html] ...etc... ] So my processing script would be like (untested) ; Get the directory directory-to-process: dirize ask "What directory?" ; Get the TOC data toc-list: GET-TOC-LIST directory-to-process ;Generate the letter TOCs (and collect the file names for later) toc-file-list: make block! (divide length? toc-list 2) foreach [toc-heading toc-links] toc-list [ toc-file: join to-file toc-heading %.html append toc-file-list toc-file ; Save the name for later. write (join directory-to-process toc-file) (MAKE-TOC-HTML toc-heading toc-links) ] ; Generate the main TOC write (join directory-to-process %toc.html) (MAKE-TOC-HTML "Alphabetical TOC" toc-file-list print "Whohoo finished!" Ok so I leave it to you now to decide if you want to go this route. If you do I suspect you will have not have much trouble with MAKE-TOC-HTML. For GET-TOC-LIST here a couple of tips 1) append/only result-block reduce [current-character file-list-block] 2) You don't necessarily need to to-string a file. For example, try this first first read %. Ok the code now maybe be bigger than your original script, but look what you get. You can process any directory and the logic of the script almost jumps out at you when you read it. Also you get the chance now that you might like to add some extra capabilities using some refinements on the functions. Second last point ;) When you make changes to a working script that you want to stay working, implement only one change at a time across the script and test it. This incremental way of changing your script is the safest way to "refactor". Last point. One of the "refactorings" with the biggest payback is to change variable names to something meaningful. Just making this one change across scripts can be extremely illuminating. The script starts to tell you about itself. [It's ok, I'm not crazy yet ;)] Just some simple ideas, but with big payoffs. I hope they are of value to you. Brett.

 [3/3] from: sharriff:aina:med-iq at: 17-Nov-2000 15:55


! ! Thanks Brett, Ill do my best to adhere to the principles you stated. My other script is in the trash, and Im starting afresh. Sharriff Aina med.iq information & quality in healthcare AG