Re: Questions about git-rev-parse

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Feb 28, 2007, 03:33 UTC
Message-ID: <Pine.LNX.4.64.0702271921110.12485@woody.linux-foundation.org>
In-Reply-To: <20070228025258.GD2178@thunk.org>

On Tue, 27 Feb 2007, Theodore Tso wrote:

> 
> So while I'm asking questions, where did the "*-ish" terminology come 
> from, anyway?

It's means "approximate" or "having the character of". Quite like the normal English meaning of "thirtyish" or "fortyish" when you talk about approximate ages of people, or "tallish" when you talk about height. Google for "ish suffix", and you'll get as your first hit:

	http://www.randomhouse.com/wotd/index.pperl?date=19990617

and the git usage is actually just a variation of that.

So a "tree-ish" is not necessarily exactly a tree, but it has all the characteristics of a tree (by virtue of there being a well-defined 1:1 relationship with a tree).

> I had the mental model (which I had intuited, since no git documentation 
> I could find had bothered to explain it) that -ish meant something like 
> specifier, so "tree-ish" meant tree specifier, so a commit id could get 
> dereferenced into a tree id, so it could be used to specify a tree.

No, it really is English. At least grammatically.

A "tree-ish" is "like a tree", exactly like "sheepish" is "like a sheep". Nothing really git-specific about it, except for it certainly having become common usage in a way that it may not be normally ;)

		Linus