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

> -	Instead of using the default 7 hexadecimal digits as the
> -	abbreviated object name, use <n> digits, or as many digits
> -	as needed to form a unique object name.  An <n> of 0
> -	will suppress long format, only showing the closest tag.
> +	Instead of using the default number of hexadecimal digits (which
> +	will vary according to the size of the repository with a default of
> +	7) of the abbreviated object name, use <n> digits, or as many digits
> +	as needed to form a unique object name.  An <n> of 0 will suppress
> +	long format, only showing the closest tag.
>   

>   --candidates=<n>::
>   	Instead of considering only the 10 most recent tags as
> @@ -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.