On 2022/03/21 05:45, Andreas Luik wrote:
Description:
Bash fails to correctly test for parameter to be unset or null when the
parameter is an array reference [*] or [@].
Repeat-By:
myvar[0]=
echo "${myvar[0]:+nonnull}"
<empty> -> OK
echo "${myvar[*]:+nonnull}"
nunnull -> not OK, because "${myvar[*]}" is null
myvar[*] = ('', ) element 0 contains an empty string, so not null.
echo "${myvar[@]:+nonnull}"
nunnull -> likewise not OK, because "${myvar[@]}" is null
myvar[@] = '' (displays all elements, each quoted. Since
element 1 contains an empty string, it is quoted and isn't null.
