DB<145> %h=(a=>1,b=>2,c=>3)
 => ("a", 1, "b", 2, "c", 3)

  DB<146> @keysToDelete=qw/b c d/
 => ("b", "c", "d")

  DB<147> delete @h{@keysToDelete}
 => (2, 3, undef)

  DB<148> \%h
 => { a => 1 }