$ perl -MO=Concise,-exec -e'@b = sort foo @a'
1  <0> enter
2  <;> nextstate(main 1 -e:1) v
3  <0> pushmark s
4  <0> pushmark s
5  <$> const[PV "foo"] s/BARE
6  <#> gv[*a] s
7  <1> rv2av[t4] lK/1
8  <@> sort lKS
9  <0> pushmark s
a  <#> gv[*b] s
b  <1> rv2av[t2] lKRM*/1
c  <2> aassign[t5] vKS
d  <@> leave[1 ref] vKP/REFC
-e syntax OK