Re: Inefficient code in reftex-index.el

[Richard Stallman]

    > Can't you tell that more easily by seeing if match-beginning returns nil?

    Which match-beginning?

One for a subexpression inside the alternative you're trying to test for.

    After (string-match "\\(a\\)\\|\\(b\\)\\|\\(c\\)" input)

    I can just consult (length (match-data)) for distinguishing between
    all three alternatives.

You could, but you'd have to compare the value of that against various
constants, which would be ugly.  I think this code is cleaner:

   (cond ((match-beginning 1)
          ...)
         ((match-beginning 2)
          ...)
         ((match-beginning 3)
          ...)