(define-record-type :rule-cand
(make-rule-cand target prereqs up-to-date?-func build-func)
is-rule-cand?
(target rule-cand-target)
(prereqs rule-cand-prereqs)
(up-to-date?-func rule-cand-up-to-date?-func)
(build-func rule-cand-build-func))