Re: recentf exclude question

["B. T. Raven" <nihil@nihilo.net>]

Andreas Politz wrote:
> "B. T. Raven" <nihil@nihilo.net> writes:
> 
>> Andreas Politz wrote:
>>> "B. T. Raven" <nihil@nihilo.net> writes:
>>>
>>>> I want only .txt, .tex, and the .emacs files listed in recentf (under
>>>> Open Recent). Is there some way to construct a regular expression to
>>>> prevent other opened files from being added to the list?
>>>>
>>>> Thanks,
>>>> Ed
>>> Try this.
>>>
>>> (setq recentf-exclude nil
>>>       recentf-include '("\\.t\\(ex\\|xt\\)\\'" "\\`\\.emacs\\'"))
>>>
>>> -ap
>>>
>>>
>>>
>> I find a recentf-keep variable in vers. 22 and 23 but no
>> recentf-include. Anyway I evaluated the expression but it didn't
>> prevent any types of files from being added to the list. Your first
>> regular expression in the list with bar disjunction doesn't have a
>> backtick to match the tick before the double quote; is this on
>> purpose? I don't see how the first regexp specifies any number of
>> characters before tex or txt and the second no characters. It looks
>> like tex and txt are kept if I change the variable in your expression
>> to recentf-include but .emacs isn't added to the list.
>>
>> ???
>>
>> Ed
> 
> \` and \' match at the beginning and end of a string or buffer.
> 
> The regexp does not necessarily have to match the whole file-name.
> 
> Yes, it's called recentf-keep.
> 
> Yes,the \` before .emacs is to restrictive, remove it. Or replace it
> with [/\\] (match directory separator character).
> 
> -ap

Thanks, Peter and Andreas. This expression filters out what I want to 
ignore:

(setq recentf-exclude nil
       recentf-keep '("\\.t\\(ex\\|xt\\)\\'" "\\.emacs\\'"))

If I do this through Custom I guess I don't need (and can't use the bar 
expression) the escape mechanism to prevent inappropriate interpretation 
by the lisp reader. Do I just set recentf-exclude to nil and use the 
three strings ".txt" ".tex" and ".emacs" in Customize or can the same 
regexps in the setq be used there too?

Ed