On Sun, Oct 29, 2017 at 10:44 PM, Clark Wang <dearv...@gmail.com> wrote:
>
> Different people have different expectations which they believe are
> all important.
Yes, and I have already went over this several times: this is an issue
that does confuse people, both ones that I have spoken to and in
tutorial/example/etc pages that come up on top when searching.
> It's not possible to cover so many tricky things in the manual.
It definitely is; it's a tradeoff between things that are worth
mentioning and the size becoming big enough that people won't bother
reading it, hence I tried to suggest a very small change.
> To me the most important thing is to describe the syntax correctly.
This is a non-point. I obviously don't think that some explanation
should be added *instead* of existing descriptions, or instead of the
current completeness level.
> When you understand the syntax "unset arr[i]" would never surprise
> you.
Again, `unset` has different expectations, because it seems like it
would be a special construct -- since it's dealing with *lvalues*. Like
I said, the other place where array reference lvalues appear in bash,
assignments, do treat these "lvalue expressions" differently, and even
though it is for a different reason, it makes it easier to get confused
and assume that `unset` is special too. To summarize:
* In assignments like a[0]=foo, the a[0] part is treated in a special
way because otherwise it will not be an assignment. Specifically,
quoting the whole "a[0]" is not needed, and adding it will break in an
obvious way.
* In plain variable referendces, $a[0] is wrong anyway, and in ${a[0]}
there is no need to quote the a[0] since no path expansion is done
there anyway, and, again, it will break in an obvious way.
* The last kind of reference is unset, and after the above two it is
reasonable to assume that it *will* be special and will not require
quoting as well. That's why I think that a warning that it is not
special is warranted.
Yet another way to phrase the above: I don't think that you can mess up
these assignments or references with a file like "a0"; but you can do so
for `unset`.
--
((x=>x(x))(x=>x(x))) Eli Barzilay:
http://barzilay.org/ Maze is Life!
