Re: [TxMt] match and look ahead?

On Mon, Sep 5, at 3:16 PM, Allan Odgaard wrote:

On 05/09/2005, at 21.26, Gerd Knops wrote:

...

To make it easier to visually parse blocks, I am trying to write a pattern that matches on 'even tabs' and give them a light gray background.

I tried something like match= "^(?=\t)\t"; but that doesn't seem to work. Is look ahead not possible in pattern matches?

It is, but that pattern would match the first tab on a line.

To markup leading odd/even tabs, you could use a rule like this:

{   name = "meta.leading-tabs";
    begin = "^(?=\\t)"; end = "(?=[^\\t])";
    patterns = (
        {   match = "(\\t)(\\t)?";
            captures = {
                1 = { name = "meta.odd-tab"; };
                2 = { name = "meta.even-tab"; };
            };
        }
    );
},

Fantastic! Works great and makes complex code much more readable. I use a 95% white background for the even tabs. It is subtle but extremely helpful. May I recommend that being added to all languages where it makes sense?

Gerd