On 10/19/2009 12:20 PM Alan Gauld said...
"Sander Sweers" <sander.swe...@gmail.com> wrote
mylist = ['John', 'Canada', 25, 32, 'right']
a = [item.upper() for item in mylist if type(item) == type('good')]
Usually it is recommended to use hasattr() instead of type()
hasattr(s, 'upper')
Nope, they do completely different things
I think you might be thinking of isinstance() which can be used instead
of type(). I see you use hasattr as a means of testing for a method but
that is still different from testing type - the method names might be
the same but the functions be completely different in effect!
returned this: ['JOHN', 'CANADA', 'RIGHT']
I was expecting this: ['JOHN', 'CANADA', 25, 32, 'RIGHT']
So, actually the "if" acted like a filter.
It is intended to be used as a filter.
In order to use a list comprehension I created this function instead.
def upperfy(item)
try:
item = item.upper()
except AttributeError:
pass
return item
I would move return item under the except and remove the pass, other
might disagree on this.
I would :-)
Doing that would result in None being returned for each successful
conversion. The OPs code is correct (even if unnecessary)
a = [upperfy(item) for item in mylist]
a = [item.upper() if type(item) == str else item for item in mylist]
should do it I think.
or even
a = [ str(item).upper() for item in mylist ]
Emile
HTH,
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