Re: [PATCH] describe-doc: clarify default length of abbreviation

From: Felipe Contreras <felipe.contreras@gmail.com>
Date: May 16, 2021, 18:51 UTC
Message-ID: <60a1699eedcd4_109fc7208e1@natae.notmuch>
In-Reply-To: <1dc7877e-adb4-e3f5-3b59-bd45f9673596@gmail.com>

Bagas Sanjaya wrote:

Show 14 quoted lines

> On 16/05/21 14.32, Anders Höckersten via GitGitGadget wrote:
> > @@ -139,8 +140,11 @@ at the end.
> >   
> >   The number of additional commits is the number
> >   of commits which would be displayed by "git log v1.0.4..parent".
> > -The hash suffix is "-g" + unambiguous abbreviation for the tip commit
> > -of parent (which was `2414721b194453f058079d897d13c4e377f92dc6`).
> > +The hash suffix is "-g" + an unambigous abbreviation for the tip commit
> > +of parent (which was `2414721b194453f058079d897d13c4e377f92dc6`). The
> > +length of the abbreviation scales as the repository grows, using the
> > +approximate number of objects in the repository and a bit of math
> > +around the birthday paradox, and defaults to a minimum of 7.
> 
> What is the birthday paradox then?

It's a probability fact that goes against common sense. In a romm with 23 people you are 50% likely to find two people with the same birthday.

https://en.wikipedia.org/wiki/Birthday_problem

-- 
Felipe Contreras