Re: [Help-bash] Destroying arbitrary subset in an associative array?

[Greg Wooledge]

On Sun, Sep 18, 2016 at 03:10:10PM -0400, Mingye Wang (Arthur2e5) wrote:
> a valid identifier". I am using bash 4.3.42.
> 
>       declare -A dict
>       dict['"']=1
>       dict['`']=2
>       dict["'"]=3
>       dict['\']=4
>       declare -p dict
> 
>       del(){ unset -v dict["$1"]; }
>       for k in "address@hidden"; do del "$k"; done

Dan's response was rather cryptic, but here's the informative part buried
deep inside it:

imadev:~$ bash-4.3
imadev:~$ declare -A dict
imadev:~$ dict['"']=1  dict['`']=2  dict["'"]=3  dict['\']=4
imadev:~$ dictdel() { unset -v 'dict[$1]'; }
imadev:~$ for k in "address@hidden"; do dictdel "$k"; done
imadev:~$ declare -p dict
declare -A dict='()'

Rule of thumb: never write unset foo[x].  Always write unset 'foo[x]'.

The simplest reason for this is that foo[x] is a valid glob (filename
expansion), and will be replaced by foox if there happens to be a file
by that name in $PWD.

The more complex reason is... whatever Dan said.