bash - Unset variables declared in file -


say have object.properties, looks like

test=1 hello=2 foo=3

let's these variables in environment. how can unset of them? i.e.

unset test hello foo

using simple bashfaq #1 loop:

while ifs='=' read -r key value;   unset "$key" done <object.properties

or, if have bash 4.0 or newer, can couple readarray (the shell builtin known mapfile) parameter expansion:

readarray -t lines <object.properties unset "${lines[@]%%=*}"

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