$ perl -MMemoize -MMemoize::Expire -E " \
    sub f { int rand 100 }; \ 
    tie my %cache => 'Memoize::Expire', LIFETIME => 2; \
    memoize 'f', LIST_CACHE => 'MERGE', \
                 SCALAR_CACHE => [ HASH => \%cache ]; \
    for (1..10) { say f(); sleep 1 }"
62
62
56
56
39
39
85
85
42