>perl -MO=Concise,-exec -e"while (1) {}"
1  <0> enter
2  <;> nextstate(main 3 -e:1) v:{
3  <{> enterloop(next->5 last->6 redo->4) v
4  <0> stub v
5  <0> unstack v
-e syntax OK

##</code><code>##

>perl -MO=Concise,-exec -e"for (;;) {}"
1  <0> enter
2  <;> nextstate(main 3 -e:1) v:{
3  <{> enterloop(next->5 last->6 redo->4) v
4  <0> stub v
5  <0> unstack v
-e syntax OK