Ubuntu Manpage: Lingua::DE::ASCII - Perl extension to convert german umlauts to and from ascii

Provided by: liblingua-de-ascii-perl_0.11-1_all

NAME

       Lingua::DE::ASCII - Perl extension to convert german umlauts to and from ascii

SYNOPSIS

         use Lingua::DE::ASCII;
         print to_ascii("Umlaute wie ä,ö,ü,ß oder auch é usw. " .
                        "sind nicht im ASCII Format " .
                        "und werden deshalb umgeschrieben);
         print to_latin1("Dies muesste auch rueckwaerts funktionieren ma cherie");

DESCRIPTION

This module enables conversion from and to the ASCII format of german texts.

It has two methods: "to_ascii" and "to_latin1" which one do exactly what they say.

Please note that both methods take only one scalar as argument and not whole a list.

to_ascii($string)

The "to_ascii" method is just simple. It replaces each printable ANSI character (codes
160..255) with a (hopefully) sensfull ASCII representation (might be more than one
character). The ANSI character with codes 128..160 are not printable and they are removed
by default. The transliteration is defined with the global
%Lingua::DE::ASCII::ANSI_TO_ASCII_TRANSLITERATION variable. You can change this variable
if you want to change the transliteration behaviour.

to_latin1($string)

The "to_latin1" method is very complex (more than 700 lines of code). It retranslates
7-bit ASCII representations into a reasonable german ANSI representation. Thus it changes
mainly 'ae' to 'ä', 'oe' to 'ö', 'ue' to 'ü', 'ss' to 'ß'. It also changes some other
characters, e.g. '(C)' to '©' or in words like 'Crepe' it also restores the really writing
'Crêpe'.

Of course, the method only tries to change where it should. That explains the enormous
complexity of this method, as it tries to solve a hard linguistic problem with a bit logic
and many regular expressions (please also look to BUGS if you are interested in known
problems).

It's quicker to let "to_latin1" work on a big (even multiline) string than to make a lot
of callings with little strings (like lines or words). The reason is that the method works
with a lot of regular expressions (as nearly every line of code contains a regexp). As
Perl is very good to optimize them especially for long strings, you can gain a good speed
advantage if you need it.

At the moment you can't change the behaviour of the "to_latin1" method (e.g. switching
from the new german spelling to the old one), and I'm not sure whether I will enable it.
Please inform me, if you feel that it would be important or much convenient in a case.

EXPORT

to_ascii($string) to_latin1($string)

BUGS

That's only a stupid computer program, faced with a very hard AI problem. So there will
be some words that will be always hard to retranslate from ASCII to Latin-1 encoding. A
known example is the difference between "Maß(einheit)" and "Masseentropie" or similar.
Another examples are "flösse" and "Flöße" or "(Der Schornstein) ruße" and "Russe",
"Geheimtuer(isch)" and "Geheimtür", "anzu-ecken" and "anzücken" or quite even a lonely
"ss" or "ß". Also, it's hard to find the right spelling for the prefixes "miss-" or
"miß-". In doubt I tried to use to more common word and in even still a doubt the program
tries to be conservative, that means it prefers not to translate to an umlaut. Reason is
that the text is still readable with one "ae","oe","ue" or "ss" too much, but a wrong "ä",
"ö", "ü" or "ß" can make it very unreadable.

I tried it with a huge list of german words, but please tell me if you find a bug.

This module is intended for ANSI code that is e.g. different from windows coding.

Misspelled words will create a lot of extra mistakes by the program. In doubt it's better
to write with new Rechtschreibung.

The "to_latin1" method is not very quick (but quick enough to work interactively with text
files of about 100 KB). It's programmed to handle as many exceptions as possible.

I avoided localizations for character handling (thus it should work on every computer),
but the price is that in some rare cases of words with multiple umlauts (like
"Häkeltülle") some buggy conversions can occur. Please tell me if you find such words.

The "to_latin1" method also has some knowledge to work with some basic English. (So that
some words don't confuse everything and you can also use some code snippets in your text).
However, it is very recommended to use American English instead of British English.
Espeically many plural forms (ending on "oes") are hard to handle, and often I decided not
to implement an extra rule as it is a "Lingua::DE::*" module and not an English one.

TESTS

       The test scripts (called by e.g. "make test") need a long time.  The reason is that I test
       it with a huge german word list. Normally you can skip this test if there is no failing in
       the first few seconds. However, the tests also have a progress bar (either a
       Term::ProgressBar if installed or just a simple text output), so that you can see the
       advances :-)

       There are two major reasons why I added so many words to test even to the CPAN release. On
       the one hand, I wanted to give you a chance to detect strange behaviour under uncommon
       circumstances. (I haven't test it under a non-german locale based operation system e.g.
       and I have also included that words are tests under a random environment to find out
       unexpected errors) On the other hand, I also wanted you to give a chance to detect
       yourself whether a "to_latin1" result is a bug or a feature.  (Just search through the
       content of the test files to determine whether a strange looking word is tested for and
       thus wanted).

       There is also a test with common 1000 English words (having an ae,oe,ue or ss inside), as
       German is nowadays often mixed with a lot of them, and this module should not be confused
       with them.

AUTHOR