On Tue, Jun 11, 2024 at 6:48 AM Zachary Santer <zsan...@gmail.com> wrote:
>
> The ( ) within the parameter expansion would be roughly analogous to
> the right hand side of a compound assignment statement for an indexed
> array. The values found therein would be taken as the indices of array
> elements or characters to expand. Trying to set indices for the
> indices, i.e. "${array[@]( [10]=1 [20]=5 )}", wouldn't make any sense,
> though, so not quite the same construct.
It occurs to me that, if this were to be implemented, arithmetic
evaluation should be performed on the contents of the parentheses when
this is part of an indexed array expansion, since those indices can
only be integers anyway. This would then be the same behavior you get
within
declare -i -a indeces
indeces=( 2#0010 2#1000 )
for instance.
So, "${array[@]( 2#0010 2#1000 )}" would have the same effect as
"${array[@]( "${indeces[@]}" )}", though arithmetic evaluation was
already performed when indeces[@] was assigned a value.
Is "${array[@]( "${indeces[@]}" )}" ugly? Does that matter? It seems
like a good way to write what's happening. I still have to look up
some of the less-commonly-used parameter expansions every time I use
them. I think people would kind of "get" this more readily.
