[Python-Dev] Unicode byte order mark decoding
ejones at uwaterloo.ca
Tue Apr 5 21:53:05 CEST 2005
On Apr 5, 2005, at 15:33, Walter Dörwald wrote:
> The stateful decoder has a little problem: At least three bytes
> have to be available from the stream until the StreamReader
> decides whether these bytes are a BOM that has to be skipped.
> This means that if the file only contains "ab", the user will
> never see these two characters.
Shouldn't the decoder be capable of doing a partial match and quitting
early? After all, "ab" is encoded in UTF8 as <61> <62> but the BOM is
<ef> <bb> <bf>. If it did this type of partial matching, this issue
would be avoided except in rare situations.
> A solution for this would be to add an argument named final to
> the decode and read methods that tells the decoder that the
> stream has ended and the remaining buffered bytes have to be
> handled now.
This functionality is provided by a flush() method on similar objects,
such as the zlib compression objects.
More information about the Python-Dev