Completeness theorem for parse-dash-1*digit.
Theorem:
(defthm parse-dash-1*digit-when-tree-match (implies (and (tree-match-element-p tree (!_ (/_ "-" (1*_ *digit*))) *grammar*) (tree-terminatedp tree) (mv-nth 0 (parse-digit rest-input))) (equal (parse-dash-1*digit (append (tree->string tree) rest-input)) (mv nil (tree-fix tree) (nat-list-fix rest-input)))))