Re: 'r' history parameter documentation fix

["Štěpán Němec" <stepnem@gmail.com>]

Peter Stephenson wrote: 

> Remove a filename extension leaving the root name.  Strings with no
> filename extension are not altered.  For this purpose, a filename
> extension is a `tt(.)' followed by any number characters (including
                                               ^
                                               of
> zero) that are neither `tt(.)' nor `tt(/)' and that continue to the end
> of the string.  For example, the extension of
> `tt(foo.orig.c)' is `tt(.c)', and `tt(dir.c/foo)' has no extension.

Quite clear to me. (Except that I'd still prefer just leaving the
explanation out than opening this can of worms -- for instance, although
it might seem far-fetched, the "for this purpose" thing made me wonder
"Hm, is this supposed to imply that Zsh also might have other notions of
file extensions in other contexts?" And you know, I don't really want to
know the answer. Everybody knows what a file extension is, right?)

-- 
Štěpán