On 03/17/2017 09:16 PM, Dan Douglas wrote:
> Why
> would a subshell just make the call stack go away?
I guess slight correction, it's unset itself, because:
> In fact, mksh prints "global" even without the subshell, despite it
> using dynamic scope for either function definition syntax.
Another
On 03/17/2017 07:21 PM, Stephane Chazelas wrote:
> I don't expect the need to have to add "local var" in
>
> (
>unset -v var
>echo "${var-OK}"
> )
True. I would pretty much never use a subshell command group when I know
that locals are available though. And if I know locals are available
2017-03-17 17:35:36 -0500, Dan Douglas:
> The need to localize IFS is pretty obvious to me - of course that's
> given prior knowledge of how it works.
[...]
I don't expect the need to have to add "local var" in
(
unset -v var
echo "${var-OK}"
)
would be obvious to many people beside you th
The need to localize IFS is pretty obvious to me - of course that's
given prior knowledge of how it works.
The problem is the non-obvious nature of unset's interaction with scope,
(and the lack of documentation). Not much can be done about the former,
as it is with so many things.
It's probably easiest to find previous discussions here on this topic
by searching for 'upvar' (common name for a function that takes
advantage of this behavior).
Latest I think was this one [1] but a much earlier discussion is here [2].
[1] https://lists.gnu.org/archive/html//bug-bash/2015-01/
Hi,
consider this function:
split() (
unset -v IFS # default splitting
set -o noglob # disable glob
set -- $1 # split+(no)glob
[ "$#" -eq 0 ] || printf '<%s>\n' "$@"
)
Note the subshell above for the local scope for $IFS and for
the noglob option. That's a common idiom in POSIX shells
On Tue, Mar 14, 2017 at 9:07 PM, Chet Ramey wrote:
> when PS1 is expanded the first time, the "current" history entry is the
> one corresponding to the last command entered
> PS2 looks at the current history entry, which is 530 since we've
> started on it.
I think I'm missing something. It seems
There is a parse error in B:
# A
bash$ p=; : "${p:=>(f()(echo "$@") ;f foo)}"; declare -p p
declare -- p=">(f()(echo ) ;f foo)"
bash$ p=; : ${p:=>(f()(echo "$@") ;f foo)}; declare -p p
declare -- p="/dev/fd/63"
foo
bash$ p=; echo "${p:=>(f()(echo "$@") ;f foo)}"
(f()(echo ) ;f foo)
# B
ba
