1# Exitcode 0 (`` has no exitcode, but assignment has):
2true;  a=``; echo $?
3false; a=``; echo $?
4true;  a=$(); echo $?
5false; a=$(); echo $?
6# Exitcode 2 (`cmd` expansion sets exitcode after assignment set it to 0):
7true;  a=`exit 2`; echo $?
8false; a=`exit 2`; echo $?
9true;  a=$(exit 2); echo $?
10false; a=$(exit 2); echo $?
11# Exitcode 1 (redirect sets exitcode to 1 on error after them):
12true;  a=`` >/does/not/exist; echo $?
13false; a=`` >/does/not/exist; echo $?
14true;  a=$() >/does/not/exist; echo $?
15false; a=$() >/does/not/exist; echo $?
16true;  a=`exit 2` >/does/not/exist; echo $?
17false; a=`exit 2` >/does/not/exist; echo $?
18true;  a=$(exit 2) >/does/not/exist; echo $?
19false; a=$(exit 2) >/does/not/exist; echo $?
20