>perl -MO=Concise,-exec -e"qq{\Q$x}"
1  <0> enter
2  <;> nextstate(main 1 -e:1) v:{
3  <#> gvsv[*x] s
4  <1> quotemeta[t2] sK/1
5  <@> stringify[t3] vK/1
6  <@> leave[1 ref] vKP/REFC
-e syntax OK

>perl -MO=Concise,-exec -e"quotemeta($x)"
1  <0> enter
2  <;> nextstate(main 1 -e:1) v:{
3  <#> gvsv[*x] s
4  <1> quotemeta[t2] vK/1
5  <@> leave[1 ref] vKP/REFC
-e syntax OK