$ perl -MO=Concise
my $foo = 'bar';
my $baz = "foo${foo}bar\n";

e  <@> leave[1 ref] vKP/REFC ->(end)
1     <0> enter ->2
2     <;> nextstate(main 1 -:1) v ->3
5     <2> sassign vKS/2 ->6
3        <$> const[PV "bar"] s ->4
4        <0> padsv[$foo:1,3] sRM*/LVINTRO ->5
6     <;> nextstate(main 2 -:2) v ->7
d     <2> sassign vKS/2 ->e
-        <1> ex-stringify sK/1 ->c
-           <0> ex-pushmark s ->7
b           <2> concat[t4] sKS/2 ->c
9              <2> concat[t3] sK/2 ->a
7                 <$> const[PV "foo"] s ->8
8                 <0> padsv[$foo:1,3] s ->9
a              <$> const[PV "bar\n"] s ->b
c        <0> padsv[$baz:2,3] sRM*/LVINTRO ->d
- syntax OK