in reply to v5.36 syntax error around given/when
"I know that given is still experimental (and unpopular), but I thought it was still supported by 5.36."
"... with this release, the experimental switch feature, present in every feature bundle since they were introduced in v5.10, has been removed from the v5.36 bundle. ..."
See "perlsyn: Switch Statements" for more about the switch feature.