Re: Zero Width Space (was Re: How to print a literal '.' as the first character in a line?)

[James K. Lowden]

On Thu, 5 May 2022 03:40:27 -0500
Dave Kemper <saint.snit@gmail.com> wrote:

> To cite the example that originally launched this thread, the old
> docs termed the \& a "zero width space," which Branden has changed to
> the "non-printing input break."  It may not roll off the tongue as
> easily, but it's more precise and descriptive about what the escape
> does: it affects how input is parsed, not how output is rendered.
> It's not kin to other space escapes like \~ or \|, as the original
> term implied.

I disagree.  That's not what it does.  

The zero width space does not "affect how input is parsed".  It's
parsed like all other input -- indeed, exactly like \| and \~.  Its only
distinction from them is on output.  

To insert \& at the start of a line does not affect how the input is
parsed.  *Any* character before a leading dot prevents the dot from
being interpreted as a request.  The salient difference is that \&
introduces nothing into the output stream.  Hence, "zero width".  

To me, the term "non-printing input break" verges on nonsense because
it suggests there might be such a thing as "printing input".  There is
not: input is processed and rendered as output.  Input is no
more printed than it is written to the keyboard.  

I humbly suggest on this point we return to status quo ante.  A "zero
width space" is perfectly clear terminology.  The fact that \& is used
occasionally to prevent non-requests from being interpreted as requests
is incidental, easily explained and understood.  Does anyone remember
being confused by it?   I don't.  

--jkl