Re: "printf %d ''" should diagnose the empty string

[Chet Ramey]

On 11/22/24 6:55 AM, Martin D Kealey wrote:

> For me, the most *logical* way to write zero is as the empty string, even
> if that's not the *customary* way to write it. Feel free to disagree, but
> be aware we're talking about opinions, not facts, and there are cogent
> reasoned arguments to be made both ways.

You're literally the only one making this argument. It is, indeed, your
opinion, and you seem to be soloing it.


> Where?
>
>
> Who cares? They exist, they work, and we should not break them.

Color me skeptical.

> The fact that they're hard to find - and audit - is MORE reason not to
> break them, not less. Even if it turns out that no scripts currently in use
> actually rely on this feature, having to audit every script to be sure of
> this would be an unreasonable impost.

You're making another argument against fixing bugs. I'm not going to treat
it any better than the last one.

> If you mean "prove that they exist", then:
>
>     1. I have numerous examples right here on my laptop, and also
>     2. other places I can't tell you about because of NDAs and/or my feeble
>     human memory; but

So your scripts, then.

>     3. scripts that I wrote 17+ years ago were still running at numerous
>     clients when I last checked 7 years ago; I'm sure they will still be
>     running at *some* clients, even though I'm no longer paid to support
>     them.
>     4. And since I often do a non-trivial amount of numerical calculation in
>     my scripts, some significant portion of those will rely on this behaviour.

And these scripts can't stand a warning message? Because unless you're
running with -e enabled -- which is a bad idea in itself, but that's
a topic for another time -- that's all that's going to change.


> Admittedly I'm a sample size of one, but this is one of those idioms that
> is so obvious and so useful (when considering certain kinds of problems)
> that I VERY much doubt I'm the only person ever to have made use of it.

I don't doubt that there are scripts out there that inadvertently do this,
by passing quoted unset variables as printf arguments, but I very much
doubt that the practice of writing 0 as '' in an argument to printf is
much used.

--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/

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