Merge the old lambda+list into a single OClosure object which plays both roles at the same time. Take advantage of it to provide a `cl-print-object` method so kmacro objects print nicely using the `key-parse` syntax. Also replace the old `kmacro-lambda-form` with a new `kmacro` constructor which takes a `key-parse` syntax, so that the code inserted with `insert-kbd-macro` is now more readable. * lisp/kmacro.el (kmacro): New OClosure type. (kmacro-ring-head): Use `kmacro` constructor. (kmacro-push-ring): Convert `elt` from old representation if needed. (kmacro-split-ring-element, kmacro-view-ring-2nd, kmacro-view-macro): Adapt to new representation. (kmacro-exec-ring-item): Turn into obsolete alias. (kmacro-call-ring-2nd, kmacro-end-or-call-macro): Adjust accordingly. (kmacro-start-macro): Simplify call to `kmacro-push-ring`. (kmacro): New constructor function. Replaces `kmacro-lambda-form`. (kmacro-lambda-form): Use it and declare obsolete. (kmacro-extract-lambda): Rewrite and declare obsolete. (kmacro-p): Rewrite. (cl-print-object): New method. (kmacro-bind-to-key, kmacro-name-last-macro): Simplify. * lisp/macros.el (macro--string-to-vector): New function. (insert-kbd-macro): Use it. Generate code using the `kmacro` constructor. * test/lisp/kmacro-tests.el (kmacro-tests-kmacro-bind-to-single-key): Silence warning. (kmacro-tests-name-last-macro-bind-and-rebind): Strengthen the test a bit. (kmacro-tests--cl-print): New test.