2025年8月28日(木) 17:29 Martin D Kealey <mar...@kurahaupo.gen.nz>: > On Wed, 27 Aug 2025 at 15:16, Koichi Murase <myoga.mur...@gmail.com> wrote: >> local saved=$(shopt -p cmdsubst_trailing_nls) # (assume we are in a >> function) >> shopt -s cmdsubst_trailing_nls >> foo=$(some_command ...) >> eval -- "$saved" > > Couldn't we just dictate that "local -" saves all set -o and shopt settings > (or at least all new ones going forward)?
Or `local -I BASHOPTS' (as `local -' is for preserving `$-'). I actually think it would be very useful in general. However, in the present context, even with such a feature, we still cannot simply write foo=$(some_command ...) but we need to write local - shopt -s cmdsubst_trailing_nls foo=$(some_command ...) in the general context where `cmdsubst_trailing_nls' may be changed by others. Also, existing codebases of Bash frameworks need to be updated to include local - shopt -u cmdsubst_trailing_nls at the beginning of every function using any command substitutions. It's simpler than « local saved=$(...) ... eval -- "$saved" », but the fact that existing script codebases need global updates is unchanged. -- Koichi
