Error in optparse documentation

[Shatadal]

In the python documentation section 14.3.2.6 (http://docs.python.org/
lib/optparse-generating-help.html) in the last line it is written

"options that have a default value can include %default in the help
string--optparse will replace it with str() of the option's default
value. If an option has no default value (or the default value is
None), %default expands to none."

However this is true only for python 2.4 and newer and not for older
versions. Though the documentation for optparse (section 14.3,
http://docs.python.org/lib/module-optparse.html) says that the module
is new for python 2.3, in this version a help string (default value =
intermediate) e.g.

help="interaction mode: novice, intermediate, or expert [default:
%default]"

prints

interaction mode: novice, intermediate, or expert [default: %default]

and not:

interaction mode: novice, intermediate, or expert [default:
intermediate]

Only in python 2.4 and newer do you see the help string print as

interaction mode: novice, intermediate, or expert [default:
intermediate]

I think the documentation should be modified so that it is made clear
that %default in the help string behaves as is claimed only in version
2.4 and higher.


O.S. used is RHEL 9

 

[Steven Bethard]

In the python documentation section 14.3.2.6 (http://docs.python.org/
lib/optparse-generating-help.html) in the last line it is written

"options that have a default value can include %default in the help
string--optparse will replace it with str() of the option's default
value. If an option has no default value (or the default value is
None), %default expands to none."

However this is true only for python 2.4 and newer and not for older
versions.

The optparse module is externally maintained. You should file a
documentation bug at http://optik.sourceforge.net/

STeVe

 

[John Machin]

In the python documentation section 14.3.2.6 (http://docs.python.org/
lib/optparse-generating-help.html) in the last line it is written

"options that have a default value can include %default in the help
string--optparse will replace it with str() of the option's default
value. If an option has no default value (or the default value is
None), %default expands to none."

However this is true only for python 2.4 and newer and not for older
versions. Though the documentation for optparse (section 14.3,http://docs.python.org/lib/module-optparse.html) says that the module
is new for python 2.3, in this version a help string (default value =
intermediate) e.g.

help="interaction mode: novice, intermediate, or expert [default:
%default]"

prints

interaction mode: novice, intermediate, or expert [default: %default]

and not:

interaction mode: novice, intermediate, or expert [default:
intermediate]

Only in python 2.4 and newer do you see the help string print as

interaction mode: novice, intermediate, or expert [default:
intermediate]

I think the documentation should be modified so that it is made clear
that %default in the help string behaves as is claimed only in version
2.4 and higher.

Don't think, act; submit a doc patch: """
Please add the text "New in version 2.4." to the end of the last
bullet point in [the section that you quoted].
"""
and move on.

If you are maintaining software that must work on an older version of
Python, you need to read the docs for that version, as well as the
current docs -- you can't [reasonably] expect a birth certificate
attached to each paragraph

 

[Marc 'BlackJack' Rintsch]

I think the documentation should be modified so that it is made clear
that %default in the help string behaves as is claimed only in version
2.4 and higher.

Maybe something should be added for clarity but I don't think it's an
error in the docs. You are reading documentation for Python 2.5 and
expect everything in it to work in older versions too?

Pick the right documentation from http://www.python.org/doc/versions/

Ciao,
Marc 'BlackJack' Rintsch

 

[Shatadal]

Maybe something should be added for clarity but I don't think it's an
error in the docs. You are reading documentation for Python 2.5 and
expect everything in it to work in older versions too?

Pick the right documentation fromhttp://www.python.org/doc/versions/

Thanks Marc. I did not know that documentation for previous versions
existed.