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