I'm replying to this because I ran into this same problem in a different script, but please understand that this code isn't supposed to do anything but compile.
The error is because I'm using s/// on a qw() list, not a real array. A fix (that is really a hack, IMHO) would be to change it to:
map { s/_/ /g; say $_," ice cream n cake " }
@{[qw( Now_who_dat_is_with_the Party_aint_live_without_the Whatcha
+_want_some All_the_kids_like )]};
This makes the list into an array ref ([]), then dereferences to the actual array@{}.
print pack("A25",pack("V*",map{1919242272+$_}(34481450,-49737472,6228,0,-285028276,6979,-1380265972)))