to trigger/signal a rebuild for the transition 5.8.8 -> 5.10.0.
The list of packages is computed by finding all packages which end
up having either of PERL5_USE_PACKLIST, BUILDLINK_API_DEPENDS.perl,
or PERL5_PACKLIST defined in their make setup (tested via
"make show-vars VARNAMES=...").
Collection.
The Perl 5 module Scalar::Defer exports functions for constructing
values that are evaluated on demand and to force evaluation of a
deferred value.