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Title: Fail codecs.lookup() on 'mbcs' and 'tactis'
Type: enhancement Stage:
Components: Documentation, Unicode Versions: Python 2.4
Status: closed Resolution: rejected
Dependencies: Superseder:
Assigned To: lemburg Nosy List: ajaksu2, lemburg, liturgist, loewis, vstinner
Priority: normal Keywords:

Created on 2005-08-04 14:11 by liturgist, last changed 2022-04-11 14:56 by admin. This issue is now closed.

Messages (10)
msg25983 - (view) Author: liturgist (liturgist) Date: 2005-08-04 14:11
$ python
Python 2.4.1 (#1, May 16 2005, 15:19:29)
[GCC 4.0.0 20050512 (Red Hat 4.0.0-5)] on linux2
Type "help", "copyright", "credits" or "license" for
more information.
>>> import codecs
>>> codecs.lookup('ascii')
(<built-in function ascii_encode>, <built-in function
ascii_decode>, <class encodings.ascii.StreamReader at
0xb7f1302c>, <class encodings.ascii.StreamWriter at
>>> codecs.lookup('mbcs')
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "/usr/lib/python2.4/encodings/", line
96, in search_function
    globals(), locals(), _import_tail)
  File "/usr/lib/python2.4/encodings/", line 14,
in ?
    class Codec(codecs.Codec):
  File "/usr/lib/python2.4/encodings/", line 18,
in Codec
    encode = codecs.mbcs_encode
AttributeError: 'module' object has no attribute
>>> codecs.lookup('tactis')
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
LookupError: unknown encoding: tactis
msg25984 - (view) Author: Marc-Andre Lemburg (lemburg) * (Python committer) Date: 2005-08-04 14:38
Logged In: YES 

mbcs is only available on Windows.

I'm not sure what happened to the tactis codec - it's
possible that it never got checked in.

Do you have a reference for the tactis encoding ?
msg25985 - (view) Author: liturgist (liturgist) Date: 2005-08-04 14:55
Logged In: YES 

UTF-8 is an MBCS encoding in that is is a "multiple byte
character set", right? :-)  UTF-16 is an MSCS; multiple
short character set.

There appears to have been some discussion on 'tactis' and
'tactis260' earlier in bug 854511.
msg25986 - (view) Author: liturgist (liturgist) Date: 2005-08-04 15:00
Logged In: YES 

If 'mbcs' is Windows-only, then why does it appear in the
list of registered codecs in encodings.aliases.aliases on
the Linux platform?  Shouldn't it not be registered on other
msg25987 - (view) Author: Martin v. Löwis (loewis) * (Python committer) Date: 2005-08-06 11:56
Logged In: YES 

Yes, UTF-8 is a multi-byte character set, but no, UTF-8 and
mbcs are not synonyms. See

for the documentation. encodings.aliases.aliases is no
registration - it is an alias databse. So if somebody refers
to "dbcs", this will be aliased to "mbcs". That does not
mean "mbcs" needs to be supported - it only means "dbcs" is
not supported on Linux, either.

tactis was never part of a Python release, so its lack is
not a bug.

Closing this report as invalid.
msg25988 - (view) Author: Marc-Andre Lemburg (lemburg) * (Python committer) Date: 2005-08-06 12:51
Logged In: YES 

Reopened: this is indeed a bug - the tactis codec is
referenced in the aliases table but was never added to the
encodings package.

Either the codec will have to be added, or the alias entry
msg25989 - (view) Author: liturgist (liturgist) Date: 2005-08-06 19:04
Logged In: YES 

Where is bug 854511 regarding Thai encodings?  The URL has
some discussion of this bug on TISI and ISO encodings.
msg25990 - (view) Author: Martin v. Löwis (loewis) * (Python committer) Date: 2005-08-06 19:09
Logged In: YES 

It's not a bug, it's a feature request, and it's at

I have rejected the request.
msg82196 - (view) Author: Daniel Diniz (ajaksu2) * (Python triager) Date: 2009-02-16 00:45
The 'tactis' codec is still missing, but it's not mentioned in docs

I'll close this one soon unless someone voices disagreement.
msg82267 - (view) Author: STINNER Victor (vstinner) * (Python committer) Date: 2009-02-16 20:02
It looks like few people need this codec (no message since 2005), so I 
close this feature request.

Reopen this issue if you need this codec.
Date User Action Args
2022-04-11 14:56:12adminsetgithub: 42252
2009-02-16 20:02:29vstinnersetstatus: open -> closed
nosy: + vstinner
resolution: remind -> rejected
messages: + msg82267
2009-02-16 00:45:42ajaksu2setnosy: + ajaksu2
type: enhancement
messages: + msg82196
components: + Documentation
2005-08-04 14:11:16liturgistcreate