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Re^2: Modify values of tied, split lines in a file

by glemley8 (Acolyte)
on Oct 22, 2012 at 18:51 UTC ( #1000401=note: print w/ replies, xml ) Need Help??


in reply to Re: Modify values of tied, split lines in a file
in thread Modify values of tied, split lines in a file

I appreciate your honest criticism, but it is extremely vague and not very constructive. You've told me what not to do, but not why, nor any suggestions.

I'm working on a set of scripts that were jimmy-rigged together and my task is to streamline them. They do currently work, but in a very poor manner. The input file is opened, read, and closed repeatedly during the process, which I'm working to minimize. I understand that it is not good practice to load very large files into memory, hence why I'm using Tie::File to read the input line-by-line, which is working very well. There is no risk of losing my input file, since my script creates a copy and works from it.

You seem to think I'm going to blindly forward my work without any debugging or testing. For each addition, I run multiple tests to make sure the script is moving in a positive direction and that the output data is verified. You philosophy seems to be "if it ain't broke, don't fix it". My job is to fix it and perfect it.

I invite any constructive suggestions.


Comment on Re^2: Modify values of tied, split lines in a file
Re^3: Modify values of tied, split lines in a file
by Anonymous Monk on Oct 22, 2012 at 22:42 UTC

    And I will take those rebuttals at face value and now try to address them as best I can ... since now I see that you were not the source of your problem.   Your situation is a familiar one, and if you interpret what I have said (alas, reasonably so ...) as a personal affront, then I now personally and publicly apologize for it.

    (Let me reiterate that:   my initial response, I now see, was strikerather/strike that of a horse’s asterisk.)   :*{   Okay, I said it first.   I am sorry.   May we please move on.

    The use of Tie::File is basically an in-efficient way to handle the input file, but for the moment “it is one that works” and I am not personally familiar with whether or not it loads the entire file in memory.   If it does, then that part of the program must immediately be replaced at whatever the cos might be, because it just might be the camel’s straw.

    In any case, the notion of modifying the file, if it remains a file in its present form, should be immediately and categorically excluded.   You need to consume a file as input, and to produce a file as output, without altering the input and with complete replacement of the output.   That is, if the output file in question must be of the same format and cannot possibly be, say, an SQLite database file instead.

    I cordially suggest that your task is destined to be more than “streamline.”   The best strategy would be to work with a file format that is specifically designed to be a read/write file, such as SQLite.   You definitely do not want to be working in terms of explicit print statements, even if they work “at the moment,” because they are destined to be maintenance PITAs forevermore.  

    The present modus operandi of this collection of legacy scripts is ... doomed, unsalvageable.   And so, not to be continued.   Deeper cuts, made carefully but made once, will lift this long-standing headache out of its present mire and could well dramatically transform it.   I suggest that you need to advocate for permission to make this deeper approach.

    (Please re-read the next to last sentence of paragraph #2.)

      (Damn!)   Why did Perlmonks log me out?   Those words above were mine.   But I can’t edit them now unless The Gods give them to me.

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