Re: Widths in tables

Glenn Adams (
Sun, 23 Apr 95 18:46:11 EDT

| ch /* characters */

What are "characters" in a proportional-space environment?

In general terms, Jon's inference -- that "ch" is an inappropriate
length measure -- is quite correct. And not only for the reason
he states:

1. the correct term would be "glyph" in any case, since a "character"
has no visible image (and therefore no width). [A character may be
depicted by a glyph which may have a width.]

2. certain characters are depicted by glyphs which have no inherent
width, these characters are called "non-spacing combining characters".

3. If by "ch" is meant something like "spacing glyph cells" then you
still have to contend with the non-proportional & mixed font issue.

I think you should just eliminate "ch" and employ "em" instead, since
that seems to be the only resaonable interpretation here (and even that
is problematic given that multiple font runs and/or font size runs may
appear). You might solve this by providing "max-em", "min-em", and
"avg-em" units, and then choose one of these as the default interpretation
of "em".

Glenn Adams