Re: my git problem

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Apr 28, 2008, 19:28 UTC
Message-ID: <alpine.LFD.1.10.0804281222190.3119@woody.linux-foundation.org>
In-Reply-To: <alpine.DEB.1.00.0804282012140.19187@eeepc-johanness>

On Mon, 28 Apr 2008, Johannes Schindelin wrote:

Show 7 quoted lines

> 
> On Mon, 28 Apr 2008, Andrew Morton wrote:
> > 
> > That's missing the "logical" bit :)
> 
> Heh, you're right.  I am too used to Git to think how other people would 
> feel about these things... :-)

No, you are both wrong.

You're wrong because apparently you never did abstract algebra and set theory in school.

If you know math, git actually does the rigth and very much the *logical* thing.

So ".." is a simple difference, while "..." is a more complex difference.

They mean different things for different operation types, but that is again something a math person takes for granted (ie in algebra, a "+" or "-" is just a random operation that follows certain rules: "a-b" means one thing for the set of real numbers, and something *totally* different if you are talking about set algebra).

And "diff" and "log" really are different operation types, exactly in the sense that "operations on real numbers" are different from "set operations".

A "diff" is more like a difference between two real numbers: it gives a single answer (admittedly the single answer is in a different domain from the arguments). While "log" is very close to a set operation, in that it gives a set as its result.

		Linus