ox-ascii: Convert `length' to `string-width'
* lisp/ox-ascii.el (org-ascii--current-text-width): Convert `length'
to `string-width'.
(org-ascii--build-title, org-ascii--build-toc)
(org-ascii--list-listings, org-ascii--list-tables)
(org-ascii-template--document-title)
(org-ascii-inner-template, org-ascii-format-inlinetask-default)
(org-ascii-format-inlinetask-default, org-ascii-item
(org-ascii--table-cell-width, org-ascii-table-cell)
(org-ascii--current-text-width): Likewise.
I've checked all occurrences of the function `length' in ox-ascii.el.
It turns out that the most of them are calculating the width of given
string. To support fullwidth characters, we better use `string-width'
instead of `length'.
Some characters in UCS are categorized as "East Asian Ambiguous"[1].
The return value of `string-width' with those characters depends on
how Emacs is setup. We leave those ambiguous character handling to
Emacs.
Two usages of `length' in `ox-ascii.el' were left as-is, because those
were used for:
- bullet depth calculation in `org-ascii-headline', and
- cell position calculation in `org-ascii--table-cell-width'.
[1]: http://www.unicode.org/reports/tr11/#Ambiguous