str and unicode proper usage

[gizli]

Hi all,

If an entire application operates on Unicode strings from UI to
database, is there a use case for str() and unicode() functions? The
application should be able to read/write files, open sockets and
execute external processes and parse their output. From my own
experiments, the open() command for files accepts unicode strings. I
am just wondering if there is a place where str() would have to be
used, other than the usual use case of converting a non-string python
construct (such as an integer) into a string.

The reason I am asking is, I work on a project with several other
developers and our NLS testing is not going so well. Major reason is
(I think) that there is a lot of str() functions interspersed
everywhere. So whenever a unicode character is used in those
variables, the application breaks. My recommendation to the team was
to remove these functions and only leave the necessary ones. However,
I do not have a generic answer on when a str() function is necessary.

Thanks!

 

[Dave Angel]

Hi all,

If an entire application operates on Unicode strings from UI to
database, is there a use case for str() and unicode() functions? The
application should be able to read/write files, open sockets and
execute external processes and parse their output. From my own
experiments, the open() command for files accepts unicode strings. I
am just wondering if there is a place where str() would have to be
used, other than the usual use case of converting a non-string python
construct (such as an integer) into a string.

The reason I am asking is, I work on a project with several other
developers and our NLS testing is not going so well. Major reason is
(I think) that there is a lot of str() functions interspersed
everywhere. So whenever a unicode character is used in those
variables, the application breaks. My recommendation to the team was
to remove these functions and only leave the necessary ones. However,
I do not have a generic answer on when a str() function is necessary.

Thanks!

Consider switching to Python 3.x, if you aren't using any incompatible
3rd party libraries. There, the str type is always Unicode, and
literals are interpreted as Unicode.

But if 3.x isn't an option, I'd say you only need 8bit strings when
doing I/O to 8 bit devices and files. You might also need them when
talking to a program not under your own control. But if it's feasible,
convert input data immediately to Unicode, do all your processing
(including all literal strings) in Unicode, and convert back on output.
You may also need 8bit strings for some OS calls, but if you're writing
portable code, those should be minimized.

DaveA

 

[Lie Ryan]

Hi all,

If an entire application operates on Unicode strings from UI to
database, is there a use case for str() and unicode() functions? The
application should be able to read/write files, open sockets and
execute external processes and parse their output. From my own
experiments, the open() command for files accepts unicode strings. I
am just wondering if there is a place where str() would have to be
used, other than the usual use case of converting a non-string python
construct (such as an integer) into a string.

The reason I am asking is, I work on a project with several other
developers and our NLS testing is not going so well. Major reason is
(I think) that there is a lot of str() functions interspersed
everywhere. So whenever a unicode character is used in those
variables, the application breaks. My recommendation to the team was
to remove these functions and only leave the necessary ones. However,
I do not have a generic answer on when a str() function is necessary.

Thanks!

str() is rightly renamed byte() in python 3. The new name reflects its
real role: as generic binary string. Use str()/byte() to represent
non-textual stream of binary data (e.g. audio/video stream, .doc file,
or cipher-text).