Error on arithmetic evaluation of `~0`.

[Bize Ma]

This is the third time I am reporting this issue.

This fails:

var=(hello); echo "${var[~0]}"
syntax error: operand expected ...

While this works:

var=(hello); echo "${var[ ~0]}"
hello

It is also interesting that this fails:

var=hello; echo "${var[ ~0]}"
bash: var: bad array subscript

Isn't `var[0]` valid and equivalent to `var` ?

This was "supposed" to be resolved in a dev version,
but is still present on bash 5.