Re: [GNU diff] new (?) conditional diff functionality

[Stepan Kasal]

Hello,

On Wed, Oct 29, 2003 at 07:32:43AM -0800, Paul Eggert wrote:
> diff doesn't do that now.  It does have an -I option, though, which
> may do some of what you want: it ignores changes whose lines all match
> a pattern.  If you can write a pattern that matches all lines not
> containing the tag, then you're partway there.

and if you cannot write such pattern, you can preprocess all the source
file, so that all lines not containing your tag get another special tag.

Then you can make use of -I.

The you have to remove the temporary tag from the resulting diff files.

HTH,
        Stepan Kasal