[texhax] Alignment in a \newwrite file?

[geolsoft at mail.ru]

On Fri, Aug 20, 2004 at 10:49:13PM +0200, Rodolfo Medina wrote:
> Now, I would like all the stuff that gets into bluefile.tex to be aligned
> according, e.g., to the template
> 
> \halign{#&#\cr}
> 
> , i.e. all the bluefile.tex to be structured according to that alignment
> template.
> Is it possible to achieve this, and how?


If I got you right, the following does the job:


%%%%%%%%%%%%%%%%%%%%begin of myfile.tex%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\newwrite\blue

\immediate\openout\blue=bluefile

\outer\def\putstuffoverthere#1#2{\immediate\write\blue{#1,& #2!\cr}}

\putstuffoverthere{Hallo}{folks}
\putstuffoverthere{Goodbye}{folks}

\immediate\closeout\blue

{\catcode`@=11 \halign{#&#\cr\input bluefile }}

\bye
%%%%%%%%%%%%%%%%%%%end of myfile.tex%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


(If you don't need the \catcode`@=11, the example above can
work without it)

Another solution:  if you want \halign to be written out to
bluefile.tex, try this (I use \lbracechar and \rbracechar
from eplain package):


%%%%%%%%%%%%%%%%%%%%begin of myfile.tex%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\input eplain

\newwrite\blue

\immediate\openout\blue=bluefile
{\catcode`#=11 \immediate\write\blue{\halign\lbracechar #&#\cr}}

\outer\def\putstuffoverthere#1#2{\immediate\write\blue{#1, #2!\cr}}

\putstuffoverthere{Hallo}{folks}
\putstuffoverthere{Goodbye}{folks}

\immediate\write\blue{\rbracechar}
\immediate\closeout\blue

\input bluefile

\bye
%%%%%%%%%%%%%%%%%%%%end of myfile.tex%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


(The \catcode`#=11 is to prevent TeX from doubling the `#'
in the bluefile.tex)

And another one.  Here, you can control what your alignment
entries look like by redefining \alignentry, it seems to me
more general than the previous two:


%%%%%%%%%%%%%%%%%%%%begin of myfile.tex%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\input eplain

\newwrite\blue

\immediate\openout\blue=bluefile

\outer\def\putstuffoverthere#1#2{\begingroup\toks0{#1}\toks2{#2}%
  \immediate\write\blue{\noexpand\alignentry{\the\toks0}{\the\toks2}}\endgroup}

\putstuffoverthere{Hallo}{folks}
\putstuffoverthere{Goodbye}{fo\thinspace lks}

\immediate\closeout\blue

\def\alignentry#1#2{#1,&#2!\cr}
\halign{#&#\cr\input bluefile }

\bye
%%%%%%%%%%%%%%%%%%%%end of myfile.tex%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


(The tricks with \toks0 and \toks2 are to prevent expansion
of any expandables in the text of the parameters; for
instance, the \thinspace in `Goodbye, fo\thinspace lks!'
gets written out into bluefile.tex as `\thinspace', not as
`\kern <something>')

If you need a more sophisticated processing of parameters of
\putstuffoverthere, see \writenumberedcontentsentry in
xeplain.tex of eplain package, or maybe even use their
\definecontentsfile mechanism.


Best regards,
Oleg Katsitadze