Python：内联是否打印非空字符串？

Question

I'm trying to print out just the non-empty strings in a list. I can't seem to get the below to work, what am I doing wrong??

print item in mylist if item is not ""

Answer 1

The following is invalid syntax: print item in mylist if item is not ""

You could perhaps achieve what you want using a list comprehension:

>>> mylist = ["foo","bar","","baz"]
>>> print [item for item in mylist if item]
['foo', 'bar', 'baz']

Answer 2

You could create a generator to grab the items in the list that are not empty.

nonempties = (item for item in mylist if item)

Then loop and print or join them into a string.

print ' '.join(nonempties)

Answer 3

The filter() built-in is well suited for exactly that, just pass None instead of a function:

>>> filter(None, ['Abc', '', 'def', None, 'ghi', False, 'jkl'])
['Abc', 'def', 'ghi', 'jkl']

Details at http://docs.python.org/library/functions.html