RE: keep|flush-lines, how-many to be used backward.

[Drew Adams]

> For keep-lines, flush-lines M-0 could be interpreted
> as operating on the whole buffer.  I miss this functionality very much.
> I always want for these commands to operate on the whole buffer no matter
> where point is located before calling these commands, but I need every
> time to put point to the beginning of the buffer.  With a special argument
> to operate on the whole buffer these commands will be easier to use.

I raised precisely that point, but with a different solution - see thread
"Why act from point forward by default, instead of whole buffer?"  My
proposal was to act on the whole buffer unless the region is active.

Richard answered the question Why? about the status quo (which was really
meant as Why not change?) with "historical behavior" and said he didn't want
to change it. Perhaps he will go along with your M-0 proposal. I'd rather be
able to act on the buffer without any prefix arg, but M-0 is better than
nothing - good idea.