Problem with the strip string method

[Colin J. Williams]

The Library Reference has
strip( [chars])

Return a copy of the string with the
leading and trailing characters removed.
The chars argument is a string
specifying the set of characters to be
removed. If omitted or None, the chars
argument defaults to removing
whitespace. The chars argument is not a
prefix or suffix; rather, all
combinations of its values are stripped:

>>' spacious '.strip()

'spacious'

>>'www.example.com'.strip('cmowz.')

'example'

Only the last two examples below behave
as expected.

Is it intended that the full range of
characters be handled?

Colin W.

[Dbg]>>'ab$%\n\rcd'.strip('%')
'ab$%\n\rcd'
[Dbg]>>'ab$%cd'.strip('$')
'ab$%\n\rcd'
[Dbg]>>'ab$%cd'.strip('$')
'ab$%cd'
[Dbg]>>' ab$%cd '.strip('$')
' ab$%cd '
[Dbg]>>' ab$%cd '.strip('%')
' ab$%cd '
[Dbg]>>' spacious '.strip()
'spacious'
[Dbg]>>'www.example.com'.strip('cmowz.')
'example'

[Jorge Godoy]

Colin J. Williams wrote:

Return a copy of the string with the
leading and trailing characters removed.

^^^^^^^^^^^^^^^^^^^^

Only the last two examples below behave
as expected.

They all looks OK to me.

[Dbg]>>'ab$%\n\rcd'.strip('%')
'ab$%\n\rcd'

No "%" at the beginning or end of string. Nothing changed.

[Dbg]>>'ab$%cd'.strip('$')
'ab$%\n\rcd'

No "$" at the beginning or end of string. Nothing changed. I believe that
you didn't copy this from the standard input due to the presence of "\r\n"
on the answer...

[Dbg]>>'ab$%cd'.strip('$')
'ab$%cd'

No "$" at the beginning or end of string. Nothing changed.

[Dbg]>>' ab$%cd '.strip('$')
' ab$%cd '

No "$" at the beginning or end of string. Nothing changed.

[Dbg]>>' ab$%cd '.strip('%')
' ab$%cd '

No "%" at the beginning or end of string. Nothing changed.

[Steve Holden]

Colin J. Williams wrote:

The Library Reference has
strip( [chars])

Return a copy of the string with the
leading and trailing characters removed.
The chars argument is a string
specifying the set of characters to be
removed. If omitted or None, the chars
argument defaults to removing
whitespace. The chars argument is not a
prefix or suffix; rather, all
combinations of its values are stripped:

>>' spacious '.strip()

'spacious'

>>'www.example.com'.strip('cmowz.')

'example'

Only the last two examples below behave
as expected.

Adjust your expectations. The software is correct.

Is it intended that the full range of
characters be handled?

Colin W.

[Dbg]>>'ab$%\n\rcd'.strip('%')
'ab$%\n\rcd'
[Dbg]>>'ab$%cd'.strip('$')
'ab$%\n\rcd'
[Dbg]>>'ab$%cd'.strip('$')
'ab$%cd'
[Dbg]>>' ab$%cd '.strip('$')
' ab$%cd '
[Dbg]>>' ab$%cd '.strip('%')
' ab$%cd '
[Dbg]>>' spacious '.strip()
'spacious'
[Dbg]>>'www.example.com'.strip('cmowz.')
'example'

I suspect what you need is the .replace() method.

regards
Steve
--
Steve Holden [phone] [phone]
Holden Web LLC http://www.holdenweb.com/

[Harold Fellermann]

Thanks to all respondents, Steve Holden

is right, I expected more than I should
have.

Others have explained why all your examples work as they should.
From your exmaples, it seems like you would like strip to
remove the leading and trailing characters from EVERY LINE in
your string. This can be done by the simple construct

>>my_string = ' foo \n bar '
'\n'.join(line.strip() for line in my_string.split('\n'))

'foo\nbar'

If you need this construct at several places, define a function

def line_strip(string,sep='\n') :
return sep.join(line.strip() for line in string.split(sep))

cheers,

- harold -