zsh: How to check if an option is enabled

Question

To enable an option, we can use setopt. e.g.:

setopt extended_glob

How can we check if an option is currently enabled ?

Answer 1

In zsh, you can use setopt to show options enabled and unsetopt to show which are not enabled:

$ setopt
autocd
histignorealldups
interactive
monitor
sharehistory
shinstdin
zle

$ unsetopt
noaliases
allexport
noalwayslastprompt
alwaystoend
noappendhistory
autocd
autocontinue
noautolist
noautomenu
autonamedirs
.....

In bash, you can use shopt -p.

Answer 2

Just use:

if [[ -o extended_glob ]]; then
  echo it is set
fi

That also works in bash, but only for the options set by set -o, not those set by shopt. zsh has only one set of options which can be set with either setopt or set -o.

Just like with bash (or any POSIX shell), you can also do set -o or set +o to see the current option settings.

Answer 3

The zsh/parameter module, which is part of the default distribution, provides an associative array options that indicates which options are on.

if [[ $options[extended_glob] = on ]]; then …

For options that have a single-letter alias (which is not the case of extended_glob), you can also check $-.

Note that it's rarely useful to test which options are enabled. If you need to enable or disable an option in a piece of code, put that code in a function and set the local_options option. You can call the emulate builtin to reset the options to a default state.

my_function () {
  setopt extended_glob local_options
}
another_function () {
  emulate -L zsh
  setopt extended_glob
}

Answer 4

If it's only to check on terminal, I find the below helpful.

setopt | grep extended

Answer 5

() {[[ -v argv[1] && -v options[$1] ]] && echo "option <$1> is $options[$1]" || echo "no such option <$1>"  } <optname>

With <optname> from https://zsh.sourceforge.io/Doc/Release/Options.html

Examples:

() {[[ -v argv[1] && -v options[$1] ]] && echo "option <$1> is $options[$1]" || echo "no such option <$1>"  } LOCAL_TRAPS

option <LOCAL_TRAPS> is off

() {[[ -v argv[1] && -v options[$1] ]] && echo "option <$1> is $options[$1]" || echo "no such option <$1>"  } localtraps
option <localtraps> is off

() {[[ -v argv[1] && -v options[$1] ]] && echo "option <$1> is $options[$1]" || echo "no such option <$1>"  } localtrap 
no such option <localtrap>