Save As in Mountain Lion

Marco Arment on Mountain Lion’s Save As behavior:

If one edits a document, then chooses Save As, then BOTH the edited original document and the copy are saved, thus not only saving a new copy, but silently saving the original with the same changes, thus overwriting the original.

And commentary from Shawn Blanc:

Assuming this is Mountain Lion’s intentional behavior rather than a bug, then how bonkers is this?

First, in Mountain Lion, Save As saves both the new document in the new location as well as saving the state of the original. Both Shawn And Marco are using the term overwritten. And if we lived in a pre-Lion world, that word would have been accurate. Not so with the new document model.

On this site, I write a lot about videogames, and I can’t think of any better parallel than the model that many games began using years ago: auto-save. As the player moves through a level or zone, the game remembers things like position, health, and inventory status. If the player uses ammo, it’s gone because the game saved that state.

Experienced players—especially on PC—hated it. They were used to save-crawling their way through a level, being able to return to a familiar state when they had full health, plenty of items, whatever. The rest of us enjoyed knowing we could walk away at any time and come back to it right where we left off (while feeling a little dubious at first).

Mountain Lion’s Save As functionality is similar. In the old model—the one we geeks are most accustomed to—Save As would create a new file while leaving the old as you had saved it last, whenever that was.

In the old model, without versioning, this is a disaster. The system would have destroyed whatever the original file was. But not now. The new world model assumes versioning, so you can always go back to the earlier pre-overwrite version. Thats’s frustrating though, and to those still adapting from the old way, unnecessary.

Let’s take a look at what I think would be a common use case: a cover letter. I have a cover letter that I adjust in various ways when I need to apply for a job. I remove paragraphs, add details, change names, etc. Then I save it as a new document (cover letter place).

In the old model, I hit Save As and have two distinct files, letter-place1 (before changes) and letter-place2 (after changes).

Now the new model. Remember this all comes from iOS, where we think about apps first (and thus tasks or content) not files. I have letter-place1, and I already know that I’m writing a new one, so I hit Save As right away, before I’ve made any changes. Now I’ve got letter-place2 ready for changes and letter-place1 right where I left it.

This is not intended as a tutorial for people like Shawn and Marco who are both a lot more savvy than I am. It’s meant to reveal Apple’s thinking behind its new document model. It is more complicated to remember that letter-place1 was saved a week ago and that the words I just typed into it will vanish when I close that window in favor of the new one. To compare it to Marco’s overwritten, I’d use the word reverted because that’s what happens in the old model.

What we have with Mountain Lion is that your changes save, period, always (as long as it’s working properly). If you want to highlight a version or specific state, you create a new file for that version. In the mainline document (where versioning allows you to return to any specific point in time that you like) anything you do to the file saves as you go.

Interestingly, games have evolved from the early auto-save system to one very similar to what Mountain Lion does. The game is always saving for you as you go along, but if you want to preserve a specific moment (full health and ammo for instance), you must actively save a named version of that state.

It’s simpler and makes more sense if you try to let go of the age-old idea of files because as we geeks know, the Mountain Lion style “document” contains many files, from images to text to versions of those images and texts. For novices it’s brilliant. There is no save, if you will. I type, walk away, come back, and there it is, just how I left it.

If my two-year-old gets a hold of the computer and bangs away on the keyboard, it remembers what he did, but if I’ve been paying attention, I know that I can just go back (like rewind) to where I left it. Now that I think about it, the Mountain Lion model is actually better than what games have come up with, because it essentially allows for all that videogames do (auto-save plus specific named states), as well as providing virtually infinite rewind.

One document, always saving the changes you make, that’s the new model. Save As honors that idea. If you don’t want the changes to go into that document, save it as something else first. Maybe only providing Duplicate in Lion wasn’t such a bad idea after all.