[Python-Dev] [Python-checkins] r45850 - in python/trunk:Doc/lib/libfuncs.tex Lib/test/test_subprocess.py Misc/NEWSObjects/fileobject.c Python/bltinmodule.c (original) (raw)

Tim Peters tim.peters at gmail.com
Tue May 2 09:47:42 CEST 2006

SF #1479181: split open() and file() from being aliases for each other.

Umm ... why?

[/F]

so that introspection tools can support GvR's pronouncement that "open" should be used to open files, and "file" should be used as a type representing standard (current stdio-based) file handles.

Maybe some of the intended changes are missing? The post-patch docstrings don't draw this distinction, and I'm lost about what else introspection tools could be looking at to make the distinction (special-casing the names? but they could have done that before):

"""

print open.doc open(name[, mode[, buffering]]) -> file object

Open a file using the file() type, returns a file object.

print file.doc file(name[, mode[, buffering]]) -> file object

Open a file. The mode can be 'r', 'w' or 'a' for reading (default), writing or appending. The file will be created if it doesn't exist when opened for writing or appending; it will be truncated when opened for writing. Add a 'b' to the mode for binary files. Add a '+' to the mode to allow simultaneous reading and writing. If the buffering argument is given, 0 means unbuffered, 1 means line buffered, and larger numbers specify the buffer size. Add a 'U' to mode to open the file for input with universal newline support. Any line ending in the input file will be seen as a '\n' in Python. Also, a file so opened gains the attribute 'newlines'; the value for this attribute is one of None (no newline read yet), '\r', '\n', '\r\n' or a tuple containing all the newline types seen.

'U' cannot be combined with 'w' or '+' mode.

"""

In Python 2.4, the docstrings were of course the same (the current trunk's file.doc except for a line at the end). Since all useful info about how to open a file has been purged from open()'s docstring, if you've got the intent right, looks like the implementation got it backwards ;-)

OK, maybe this is what you have in mind:

type(open) <type 'builtin_function_or_method'> type(file) <type 'type'>

Fine, if that's all there really is to this, but I think it's a net loss if open()'s docstring regression stands -- someone should finish this job, or it should be reverted.

More information about the Python-Dev mailing list