Re: Rationale for split-string?

[Miles Bader <miles@gnu.org>]

On Mon, Apr 21, 2003 at 04:11:21PM -0500, Luc Teirlinck wrote:
>    (defun split-string (string &optional separators omit-nulls)
>
> There are two problems with this.  First of, all it would break tons
> of existing Emacs code.  Secondly, the defaults for SEPARATORS and for
> OMIT-NULLs do not match.  Thus, the most routine call of 
> (split-string string) would produce nonsensical results in the case of
> leading or trailing whitespace.

Other than the all-defaults case (where _both_ optional arguments are
omitted), I think Stephen's formulation is very natural, in that you usually
want OMIT-NULLS to be t if you're splitting on a non-whitespace string.

I think the problem with the all-defaults case could be solved by having
OMIT-NULLS default to t when SEPARATORS is not specified.  This is what awk
does I think (with split), and it's really very natural.

[IOW, at the beginning of the function, put:
  (unless separators (setq omit-nulls t))
]

-Miles
-- 
We are all lying in the gutter, but some of us are looking at the stars.
-Oscar Wilde