Re: Re: \nbsp usage

[Bernt Hansen <bernt@norang.ca>]

Nick Dokos <nicholas.dokos@hp.com> writes:

> Bernt Hansen <bernt@norang.ca> wrote:
>
>> Erik Butz <erik.butz@googlemail.com> writes:
>> 
>> > I want to use the \nbsp macro to generate a '~' symbol for Latex, but
>> > I don't seem to get it to work correctly in my case.
>> > I want to write 200~m=C2=B2
>> >
>> > If I do: 200\nbspm^2
>> > it gets exported as: 200\nbspm$^2$,  so the symbol is not recognized.
>> >
>> > If I do: 200\nbsp m^2
>> > it gets exported as 198~ m$^2$, so in addition to the nbsp there is
>> > another space at which a linebreak can occur
>> >
>> > trying: 200\nbsp{}m^2 in analogy to other commands
>> > I get: 200~\{\}m$^2$, so the parentheses are not recognized as
>> > belonging to the command.
>> >
>> This seems to work for me:
>> 
>> ,----[ sample org file ]
>> | * nbsp
>> | If I do: one two three four five six seven eight nine ten eleven twelve 2=
>> 00\nbsp m^2 it gets exported
>> `----
>> 
>> this exports as=20
>> 
>> ,----[ latex output ]
>> | ...
>> | \label{sec-1}
>> |=20
>> | If I do: one two three four five six seven eight nine ten eleven twelve 2=
>> 00~ m\^{}2 it gets exported
>> | \end{document}
>> `----
>> 
>> and when I look at that as a PDF it doesn't break between the 200 and
>> m^2.  I tried adding x and xx before the 200 and it pushes the entire
>> thing to the next line.  I can't make it break on a line so 200 is at
>> the end of one line and m^2 is on the following line.
>
> I suspect that you cannot decide the question with a simple experiment
> like this, but I have no counterexample to offer.
>
> However, Knuth warns explicitly (p.91 of my version of the TeXbook,
> paperback 19th printing, Oct. 1990) that "...you shouldn't leave any blanks
> next to the ~, since they will count as additional spaces."
>
> It may well be that TeX's line-breaking algorithm does the right thing in
> the example, but when push comes to shove in a *really* complicated situation,
> it might be forced to choose the space after the tilde to break the line at.

Ooops :)  Thanks for the pointer to the docs!

-Bernt