Since the advent of extended slicing, operator.isMappingType() returns a
misleading result. map(operator.isMappingType, ([], (), {}, '', u''))
[True, True, True, True, True]
I recommend removing it from the operator module.
Raymond Hettinger 3  1811 
"Raymond Hettinger" <vz******@verizon.net> wrote in message
news:vg*******************@nwrdny01.gnilink.net... Since the advent of extended slicing, operator.isMappingType() returns a
misleading result.
map(operator.isMappingType, ([], (), {}, '', u'')) [True, True, True, True, True]
I recommend removing it from the operator module.
I get the following on 2.2.3:
map (operator.isMappingType,([], {}, (), ", u"))
[0, 1, 0, 0]
Where did the fifth True come from? That's really odd!
How much code would removing it break, versus
changing the test so it looked for one or more of the
methods that's unique to maps, and not to other
kinds of sequences? Granted, testing for something
other than a magic method would slow it down, but
that should be better than either leaving it broken,
or breaking otherwise innocent code.
John Roth
Raymond Hettinger
John Roth wrote:
"Raymond Hettinger" <vz******@verizon.net> wrote in message
news:vg*******************@nwrdny01.gnilink.net... Since the advent of extended slicing, operator.isMappingType() returns a
misleading result.
>> map(operator.isMappingType, ([], (), {}, '', u''))
[True, True, True, True, True]
I recommend removing it from the operator module.
I get the following on 2.2.3:
map (operator.isMappingType,([], {}, (), ", u"))
[0, 1, 0, 0]
Where did the fifth True come from? That's really odd!
Raymond used pairs of single quotes, while you used only
individual double-quotes surrounding a string containing
a comma, a space, and the letter u. His had an empty
string and an empty unicode string...
-Peter
"Peter Hansen" <pe***@engcorp.com> wrote in message
news:3F***************@engcorp.com... John Roth wrote:
"Raymond Hettinger" <vz******@verizon.net> wrote in message
news:vg*******************@nwrdny01.gnilink.net... Since the advent of extended slicing, operator.isMappingType() returns
a misleading result.
>>> map(operator.isMappingType, ([], (), {}, '', u''))
[True, True, True, True, True]
I recommend removing it from the operator module.
I get the following on 2.2.3:
>> map (operator.isMappingType,([], {}, (), ", u"))
[0, 1, 0, 0]
Where did the fifth True come from? That's really odd!
Raymond used pairs of single quotes, while you used only
individual double-quotes surrounding a string containing
a comma, a space, and the letter u. His had an empty
string and an empty unicode string...
I see. That did look odd...
John Roth
-Peter This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
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