Eric, For someone moving from other languages (like I am) to Transcript, I believe three of the four errors you point out in your example should be obvious and the same in all languages. Those are: 1. Repeatedly accessing the same data structure (field) instead of first putting it into a variable. 2. Repeatedly updating the screen on a background process. 3. Repeatedly setting a property that only needs to be set once.
However, the "repeat with i =" form being slower than the "repeat for each" was news to me! There is nothing in the documentation, that I can find, that addresses the most efficient way, from the perspective of the engine, to write a control structure. Apparently, this is particularly true of the repeat structure. Is it also true for say the if..then structure? Is it more efficient to put your conditions into variables and then use the variables as conditions of the if...then? These are the kinds of things a newbie (like myself) would greatly appreciate being documented. This is to say, if there are two or more ways to write the same statement (as with the repeat example), then if someone knows one works faster than the rest, because of their knowledge of the inner workings of the engine, then this would be valuable to document or post. This might cut down the 300 pages. :) Jim -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Eric Chatonet Sent: Thursday, June 23, 2005 11:02 PM To: How to use Revolution Subject: Fast/slow code example (was: Re: compileIt for revolution?) Hi Christian, Le 24 juin 05 à 10:21, Langers Christian a écrit : > Could you, please, give us (newbies/intermediate scriptesr) some > examples of fast/slow script code ? They would be too many :-) In fact, the problem is often more an architecture issue than a simple code issue. But here is one tiny trivial example among thousands to give you some clues: on CheckList repeat with i = 1 to the number of lines of fld "List1" set the itemDel to tab put item 2 of line i of fld "List1" & cr after fld "List2" end repeat end CheckList Main errors in the above 4 lines are: manipulate data directly from a field (a lot of work for the engine) use the "repeat with i" form slower than the "repeat for each" form (especially noticeable with long lists) force a screen redraw at each repetition (that's the must for slowing down) set the itemDel unnecessarily at each repetition The result with 1000 lines: more than 13 seconds... Better code: on CheckList local tList, tLine, tNewList ----- put fld "List1" into tList set the itemDel to tab repeat for each line tLine in tList put item 2 of tLine & cr after tNewList end repeat put tNewList into fld "List2" end CheckList manipulate data into a variable use the "repeat for each" form use one screen redraw only set the itemDel only when needed The result with 1000 lines: less than 20 milliseconds! 650 times faster... Keep in mind that to answer correctly your request, this post should be a 300 pages book :-) May be Dan wrote it? Best Regards from Paris, Eric Chatonet. ---------------------------------------------------------------- So Smart Software For institutions, companies and associations Built-to-order applications: management, multimedia, internet, etc. Windows, Mac OS and Linux... With the French touch Free plugins and tutorials on my website ---------------------------------------------------------------- Web site http://www.sosmartsoftware.com/ Email [EMAIL PROTECTED]/ Phone 33 (0)1 43 31 77 62 Mobile 33 (0)6 20 74 50 86 ---------------------------------------------------------------- _______________________________________________ use-revolution mailing list use-revolution@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-revolution _______________________________________________ use-revolution mailing list use-revolution@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-revolution
