2017-02-28 16:18:05 -0500, Chet Ramey: [...] > > Just my personal opinion, but I think I'd rather the spec had > > been updated to accomodate the bash (and many other shells) > > behaviour rather than bash breaking its backward compatibility > > to comply to a requirement that is not particularly useful > > myself. > > That's why I made the bash-4.3 behavior available via the shell > compatibility level mechanism. [...]
That's good to have at least a mechanism to make sure scripts are not going to be broken by a future, incompatible version of the shell. Would you recommend people start adding: shopt -s compat44 2> /dev/null || true at the start of their script that they develop for bash-4.4 now so that it still works even when bash-6.0 makes a non-backward compatible change? It seems there's a compatXX option for each of the versions since bash31. Will you keep doing it for every version? Maybe a shopt -s compat=44 to avoid filling up the option namespace would be better. It's not clear what combining several compat options could do. For instance with shopt -s compat31 compat43 would not be compatible with bash-4.3 in that the [[ =~ ]] operator would work the bash-3.1 way. That could cause confusion. (or #! /bin/bash -o compat=4.4 or --compat=4.4 to link to a parallel thread here). -- Stephane
