[ python-Feature Requests-1001895 ] Adding missing ISO 8859 codecs, especially Thai

Thu Aug 5 14:44:19 CEST 2004

Feature Requests item #1001895, was opened at 2004-08-02 11:48
Message generated for change (Comment added) made by lemburg
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>Category: Unicode
Group: None
>Status: Closed
>Resolution: Accepted
Priority: 5
Submitted By: Peter Jacobi (peter_jacobi)
Assigned to: M.-A. Lemburg (lemburg)
Summary: Adding missing ISO 8859 codecs, especially Thai

Initial Comment:
As the missing ISO 8859 codecs, (11:Thai, 16:Romanian) 
can be automatically generated from the Unicode 
mapping files (via gencodec.py), I'd like to ask for 
inclusion in the next version.

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>Comment By: M.-A. Lemburg (lemburg)
Date: 2004-08-05 14:44

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Checking in Misc/NEWS;
/cvsroot/python/python/dist/src/Misc/NEWS,v  <--  NEWS
new revision: 1.1073; previous revision: 1.1072
done
Checking in Lib/encodings/aliases.py;
/cvsroot/python/python/dist/src/Lib/encodings/aliases.py,v 
<--  aliases.py
new revision: 1.27; previous revision: 1.26
done
RCS file:
/cvsroot/python/python/dist/src/Lib/encodings/iso8859_11.py,v
done
Checking in Lib/encodings/iso8859_11.py;
/cvsroot/python/python/dist/src/Lib/encodings/iso8859_11.py,v
 <--  iso8859_11.py
initial revision: 1.1
done
RCS file:
/cvsroot/python/python/dist/src/Lib/encodings/iso8859_16.py,v
done
Checking in Lib/encodings/iso8859_16.py;
/cvsroot/python/python/dist/src/Lib/encodings/iso8859_16.py,v
 <--  iso8859_16.py
initial revision: 1.1
done
RCS file:
/cvsroot/python/python/dist/src/Lib/encodings/tis_620.py,v
done
Checking in Lib/encodings/tis_620.py;
/cvsroot/python/python/dist/src/Lib/encodings/tis_620.py,v 
<--  tis_620.py
initial revision: 1.1
done

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Comment By: M.-A. Lemburg (lemburg)
Date: 2004-08-05 14:33

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Nevermind. I'll also add a proper tis_620.py codec.

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Comment By: M.-A. Lemburg (lemburg)
Date: 2004-08-05 14:15

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I found these references for iso-8859-11:

iso_8859-11:1992 (try searching for this in goole :-)
http://mnogosearch.kn.vutbr.cz/Download/snapshot/mnogosearch32/src/uconv-alias.c

windows-874
http://www.memecode.com/site/ver.php?id=94

thai
windows-874
tis-620
iso-8859-11:2001
http://de.wikipedia.org/wiki/ISO_8859-11

The lsat URL suggests that iso-8859-11 is the same as tis-620,
but only the "basis" for windows-874. It also quotes the
year 2001 as the last revision of the mapping which
corresponds to the header of the Unicode mapping file.

I think it's safe to add the alias for tis-620 even though
the iso mapping has one more character. According to Google
that encoding name is much more popular than the iso one.

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Comment By: Martin v. Löwis (loewis)
Date: 2004-08-05 13:41

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The unfortunate problem is that ISO-8859-11 is not a
IANA-registered character set. For ISO-8859-16,

http://www.iana.org/assignments/character-sets

lists:

Name: ISO-8859-16
MIBenum: 112
Source: ISO
Alias: iso-ir-226
Alias: ISO_8859-16:2001
Alias: ISO_8859-16
Alias: latin10
Alias: l10 

I believe ISO-8859-11 does not have any aliases. Some people
may claim TIS-620 is an alias, but it is not (as it does not
contain \xa0).

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Comment By: M.-A. Lemburg (lemburg)
Date: 2004-08-05 13:15

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Thank you. 

Please also provide suitable aliases (I couldn't find any on
the IANA site), then I'll add them to Python 2.4.

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Comment By: Peter Jacobi (peter_jacobi)
Date: 2004-08-04 00:58

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Attached are the output if gencodec.py for ISO-8859-11, 
ISO-8859-16 and for reference also the original mapping files.

Peter

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Comment By: M.-A. Lemburg (lemburg)
Date: 2004-08-03 16:34

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Peter, could you attach the generated codecs to this report ?

Thanks.

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Comment By: M.-A. Lemburg (lemburg)
Date: 2004-08-02 13:14

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Martin, I think it's a good idea to add the codecs for
completeness. 

We should probably also review the mapping files posted on
the unicode.org site every now and then and update the
codecs in Python accordingly. Sticking to the Unicode
Consortium's view of things is a good way to assure
compatibility with other applications, IMO.

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Comment By: Martin v. Löwis (loewis)
Date: 2004-08-02 12:30

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Marc-Andre, should we add these?

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Comment By: Peter Jacobi (peter_jacobi)
Date: 2004-08-02 12:16

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In a thread on news://comp.lang.python I was asked by 
Martin v. Löwis to provide evidence on the correctness of the 
ISO 8859-11 Unicode mapping file, as found on 
ftp://ftp.unicode.org/Public/MAPPINGS/ISO8859/8859-11.TXT 
(due to the disclaimer boilerplate in these files).

So far I can provide these three points:
a) ISO 8859-n vs ISO-8859-n
If the information at http://en.wikipedia.org/wiki/ISO_8859-
1#ISO_8859-1_vs_ISO-8859-1 is correct, Python 8859-n 
codecs do implement the ISO standard charsets ISO 8859-n 
in the specialized IANA forms ISO-8859-n (and in agreement 
with the Unicode mapping files). So any difficult C0/C1 
wording in the original ISO standard can be disregarded.

b) libiconv ISO 8859-11
The implementation by Bruno Haible in libiconv does agree 
with the Unicode mapping file:
http://cvs.sourceforge.net/viewcvs.py/libiconv/libiconv/lib/

c) IBM ICU4C
The implementation in ICU4C does agree with the Unicode 
mapping file:
http://oss.software.ibm.com/cvs/icu/charset/data/ucm/

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