Re: [A-Z], [:upper:]

[Robert Elz]

    Date:        Fri, 29 Mar 2019 08:41:49 -0400
    From:        Greg Wooledge <wooledg@eeg.ccf.org>
    Message-ID:  <20190329124148.a3t3xkze4btskljb@eeg.ccf.org>

  | But perhaps you're right about the letter C specifically.

I was, because that was the character of relevance in the bug
report, and solving (or inventigating) the actual problems reported
is what ought to be done - not imaginng what the underlying problem
might be, and guessing at what might be the cause of that.

  | Now, for the original poster: the meaning of [A-Z] and [a-z] did in
  | fact change between bash 4 and bash 5.

Sure, but as the character was C, this doesn't matter.   Just as
in generla using [A-Z] isn't always a very good idea - here it did not
matter.

>From the earlier message:

  | The example is clearly contrived just for the bug report and is a
  | simplification of some existing code.

Yes, most likely.   But all we can reliably do is investigate the
actual case that is stated to fail.   Having a complex test case
simplified down to the simplest case that fails that can be found is
always helpful - and when users can do that, it is good.

But we must resist:
  | That existing code probably 

that's just guesswork and is an extreme waste of time.   If the
example in the bug report hadn't been properly tested, we should get
an update, with the actual issue in it.   If that was really it,
then we know what the problem was (but not the bash4/5 difference reported).

wooledg@eeg.ccf.org said:
  | Quoting is *the* number one issue in shell scripting.  It cannot be
  | reiterated enough.  God knows we've tried, and it's still not enough. 

Yes, I know it is a very common problem.    But by overdoing the
complaints - inventing quoting issues when there are none - you're
doing the message a disservice.   The users are not all complete
idiots - they know (occasionally) that quoting is not needed, and
when you tell them that they should add quotes they ignore you, then,
and possiblt, also some other time when quotes are really needed.

Keep the "should be quoted" for examples where it is actually
required, and just ignore that issue when it clearly is not.  Then
people will take the message more seriously.

Or in other words, evangalists get ignored by most rational people,
whatever the topic.

kre