[Help-bash] Inconsistent results of `trap '' EXIT`

[Peng Yu]

The following code shows that `trap '' EXIT` has a different effect
that depends on whether it has been set before. It is better to make
`trap '' EXIT` reset the signal instead of using `trap - EXIT`?

$ trap -p EXIT
$ trap 'echo abc' EXIT
$ trap -p EXIT
trap -- 'echo abc' EXIT
$ trap '' EXIT
$ trap -p EXIT
trap -- '' EXIT

-- 
Regards,
Peng