Is there way to put hard space after defined words?

Question

In Polish typography, one should avoid putting prepositions at the end of the line.
Example:
Nie wiedziałem, że nie umieszcza się przyimków na
końcu strony. - bad
Nie wiedziałem, że nie umieszcza się przyimków
na końcu strony. - good

Can I force LaTeX to put ~ after every word that is a preposition (e.g. w, z, na, o etc...) so I don't need to put them manually?

Answer 1

Well, I know about a few "solutions" (in quotation marks, since - as was mentioned in the comments - this is something quite difficult to do automatically).

1. The impnattypo package (http://ctan.org/pkg/impnattypo). Requires lualatex, and (among other interesting things) puts hard spaces after one-letter words. (Notice that your example was hypercorrect (see http://en.wikipedia.org/wiki/Hypercorrection), in a sense that in fact you may put "na" at the end of the line in Polish typography (as opposed to "a", "i", "o", "w" and "z"; I'm not sure about "we" and "ze"). While putting a tie ("~") after "na" etc. might be a good idea in some cases, I wouldn't advise to do it automatically - it'd be better to have each case judged by a human.)

2. There is a set of macros (for plain or LaTeX, I believe) by Przemysław Scherwentke, described in the GUST Bulletin 23 (2006), pp. 109-110. AFAIR they work even with plain vanilla Knuthian TeX, but do their job by messing with active characters, which might be a bit dangerous. AFAIK it is not available on the web, but I could scan it for you and send in an email if you want.

3. And finally, there are numerous scripts and plugins for editors to do this. As a heavy emacs addict, I know only of (two) emacs solutions. There is sierotki.el, which does two things: first, it may make your space key "electric", so that a space after a one-letter word automatically becomes a tie; second, it has a function tex-hard-spaces, which does a query-replace-regexp with suitable parameters. Actually, in current versions of sierotki.el, tex-hard-spaces is just an alias for the latter solution: tildify-buffer, which is a better one, since it can automatically detect things like math mode or verbatim, and not touch these. One (very little) problem with tildify-buffer might be its default configuration, which is suited for the Czech language; however, adapting it to Polish is a question of editing one regexp.

Answer 2

This is the mentioned style (comments are, alas, in Polish):

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% Przemyslaw Scherwentke
% Przemyslaw.Scherwentke@pwr.wroc.pl
%
% Najprostsza moľliwa (?) wersja zbioru do panowania 
% nad wiszĄcymi literami. 
%
% Rozszerzenie .STY tylko formalne
%
% Nie dzia�a z tworami typu \section.
% StĄd prze�Ączniki \spaceactive, \spacespace
% do uľycia wok˘� nich
% i analogiczna zmiana kategorii ^^M.
%
% Przyj©te sĄ pewne dodatkowe za�oľenia, 
% �atwo widoczne z kodu, w szczeg˘lno�ci
% obs�ugiwanie (formalnie) tylko podw˘jnej spacji.
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\newcount\war
\war0 

\def\spaceactive{\catcode`\ =\active}
\def\spacespace{\catcode`\ =10}
\def\CRactive{\catcode`\^^M=\active}
\def\CRCR{\catcode`\^^M=5}% oczywi�cie nie \crcr

\def~{\penalty10000\ }

\spaceactive% i teraz waľne sĄ procenty

\def #1#2#3{% moľna rozbudowa† wg wzoru
\if\noexpand \noexpand#1\advance\war4\fi%
\if\noexpand \noexpand#2\advance\war2\fi%
\if\noexpand \noexpand#3\advance\war1\fi%
\def\sprawdz##1{% tu sĄ znaki <TAB>
\ifcase##1{ }#1#2#3\relax% 0 --- #1#2#3 %bez tego \relax «le CR/LF
\or{    }#1#2{  }%  1 -- #1#2 spacja, wi©c s�owa dwuliterowe
\or{    }#1~#3% 2 #1 spacja #3
\or{    }#1~%  3 #1 spacja spacja
\or{    }#2#3% 4 spacja #2#3
\or{    }#2~% 5 spacja #2 spacja
\or{    }#3% 6 spacja spacja #3
\or{    }% 7 --- 3 spacje
\else BLAD\fi}%
\sprawdz\war%
\war0\relax}% to \relax zapobiega wch�anianiu liczb
\spacespace%
%%%%%%%
%\catcode`\^^M=\active%
\CRactive%
\newcount\warm%
\warm0%
\long\def^^M#1{%
\if\noexpand^^M\noexpand#1\advance\warm1\fi%
\def\sprawdzM##1{%
\ifcase##1\relax{   }#1% 0
\or{\par}% 1
\else{BLAD}\fi}%
\sprawdzM\warm%
\warm0\relax}%
%\catcode`\^^M=5%
\CRCR%
%%