in reply to Re: Rolling variable (Update:prime the counts file first!)
in thread Rolling variable

The first time you run this you will get an error because the file counts doesn't exist.

Also, do you mean to have both @F and @f?

Running this on my machine adds nothing to the file.

$ pwd
/Users/nick/monks
$ ls | wc -l
    39
$ perl -i'*' -anle"@f=</Users/nick/monks/*>; shift @F; push @F, scalar
+ @f; print join ' ', @F;" counts
$ cat counts
$

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The way forward always starts with a minimal test.

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Re^3: Rolling variable
by BrowserUk (Patriarch) on Jul 30, 2015 at 17:07 UTC
    The first time you run this you will get an error because the file counts doesn't exist.

    Yep. You need to prime it:echo 0 0 0 0 0 0 0 0 >counts

    do you mean to have both @F and @f?

    Yes. @F comes from -a (autosplit: see perlrun). @f is the array that gets the list of files; rename to your preference.

    Anyone got any experience of this phone's predecessor?

    With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
    Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
    "Science is about questioning the status quo. Questioning authority". I knew I was on the right track :)
    In the absence of evidence, opinion is indistinguishable from prejudice.
    I'm with torvalds on this Agile (and TDD) debunked I told'em LLVM was the way to go. But did they listen!
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[d/l]
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      It's rather a large omission to leave off half of the job ("priming" the file). I would have thought it merited an "oh crap, you're right, I forgot to say ..." rather than a "yep". Surely you don't mean to imply that anyone reading your one-liner should have known how to "prime" the file?

      Perhaps you can look at that one-liner and read it without thinking about it. Most people can't. I don't see the benefit to making code so concise that you have to refer to documentation to decipher it when you revisit crontab in a couple of months. In the case of a novice programmer asking for advice on how to perform a simple task, it seems to be mostly grandstanding, and is not helpful. If you want to share advanced techniques in a thread such as this, you should explain them.

      The way forward always starts with a minimal test.
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[d/l]
        making code so concise that you have to refer to documentation to decipher it when you revisit crontab in a couple of months. ... advanced techniques ... you should explain them

        If I (try to) explain the techniques; I expend considerable time and effort (trying to) replicate the information in the documentation; and trying to cover off every thing that the OP might not know. And then the OP will opt for one of the other solutions anyway.

        However, if I wait for the OP to ask for an explanation of the things he doesn't understand; I can point him at the appropriate documentation.

        Saves me wasting effort; and encourages the OP to learn his way around the documentation; and, when he looks in crontab(???) in a couple of months from now; he'll probably remember where to look to refresh his memory for the bits he's forgotten.

        Anyone got any experience of this phone's predecessor?

        With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
        Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
        "Science is about questioning the status quo. Questioning authority". I knew I was on the right track :)
        In the absence of evidence, opinion is indistinguishable from prejudice.
        I'm with torvalds on this Agile (and TDD) debunked I told'em LLVM was the way to go. But did they listen!
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