Re: Exposing buffer text modifications to Lisp

[Ihor Radchenko]

Eli Zaretskii <eliz@gnu.org> writes:

> Btw, do we have recipes for measuring the effects of changing the data
> structures used for markers?  If we do have such recipes, did someone
> try to compare the performance in plain-ASCII Org buffers (where the
> conversion is trivial and shouldn't even access the markers) and
> non-ASCII buffers?  Inserting a single non-ASCII character somewhere
> in an otherwise plain-ASCII buffer should show the effect of many
> markers on the likes of CHAR_TO_BYTE.

AFAIK, buf_bytepos_to_charpos should take no time on plain-ASCII buffers
because

  /* If this buffer has as many characters as bytes,
     each character must be one byte.
     This takes care of the case where enable-multibyte-characters is nil.  */
  if (best_above == best_above_byte)
    return bytepos;

The recipe of measuring the effects is in
https://list.orgmode.org/orgmode/scedec$2g0$1@ciao.gmane.io/

That email literally provides Elisp code to run in order to measure the
effect.

Best,
Ihor