Re: Negative occur

[Ted Zlatanov <tzz@lifelogs.com>]

On Wed, 28 Nov 2007 09:03:17 -0800 "Drew Adams" <drew.adams@oracle.com> wrote: 

DA> On Wed, 28 Nov 2007 11:21:43 +0100 David Kastrup <dak@gnu.org> wrote: 
>> > You could try running "occur" with the pattern "^" (which matches
>> > every line), then prune the results with M-x delete-matching-lines RET

DA> I realize that your suggestion is that this be added to Emacs. I agree.

DA> FYI - In Icicles, just do this:  C-' foobar C-~

DA> That shows and lets you visit all lines that do not match the regexp
DA> "foobar". `C-'' is `icicle-occur'. `C-~' complements the current set of
DA> matches.

Both solutions will be slower on a large buffer than they should be.  A
real inversion parameter, either as a predicate function or a variable,
passed lexically or as a parameter to the occur-engine function call, is
necessary.  A predicate function is probably best as it can express
transformations more complex than identity and negation.

Ted