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When splitting an empty string in Python, why does split() return an empty list while split('\n') re
... gives two pieces. Making two cuts, gives three pieces.
And so it is with Python's str.split(delimiter) method:
>>> ''.split(',') # No cuts
['']
>>> ','.split(',') # One cut
['', '']
>>> ',,'.split(',') # Two cuts
['', '', '']
Question: And is there ...
Is nested function a good approach when required by only one function? [closed]
...defined or used.
Update:
Here's proof that nesting them is slower (using Python 3.6.1), although admittedly not by much in this trivial case:
setup = """
class Test(object):
def separate(self, arg):
some_data = self._method_b(arg)
def _method_b(self, arg):
return arg+1
...
Pass a parameter to a fixture function
I am using py.test to test some DLL code wrapped in a python class MyTester.
For validating purpose I need to log some test data during the tests and do more processing afterwards. As I have many test_... files I want to reuse the tester object creation (instance of MyTester) for most of my tests.
...
PyCharm shows unresolved references error for valid code
...ghting my valid code with "unresolved reference" errors, even for built-in Python functions. Why don't these seem to be detected, even though the code runs? Is there any way to get PyCharm to recognize these correctly?
...
Difference between staticmethod and classmethod
... function into a class because it logically belongs with the class. In the Python source code (e.g. multiprocessing,turtle,dist-packages), it is used to "hide" single-underscore "private" functions from the module namespace. Its use, though, is highly concentrated in just a few modules -- perhaps an...
Shell脚本编程30分钟入门 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...的解释型语言都是可以用作脚本编程的，如：Perl、Tcl、Python、PHP、Ruby。Perl是最老牌的脚本编程语言了，Python这些年也成了一些linux发行版的预置解释器。
编译型语言，只要有解释器，也可以用作脚本编程，如C shell是内置的（/...
How to check a string for specific characters?
How can I check if a string has several specific characters in it using Python 2?
5 Answers
...
Difference between __str__ and __repr__?
What is the difference between __str__ and __repr__ in Python?
23 Answers
23
...
How do I check if a variable exists?
...d is likely to result in unpredictable behaviour.
If you need to do it in Python, the following trick, which is similar to yours, will ensure that a variable has some value before use:
try:
myVar
except NameError:
myVar = None
# Now you're free to use myVar without Python complaining.
H...
Pip install Matplotlib error with virtualenv
...
Building Matplotlib requires libpng (and freetype, as well) which isn't a python library, so pip doesn't handle installing it (or freetype).
You'll need to install something along the lines of libpng-devel and freetype-devel (or whatever the equivalent is for your OS).
See the building requirem...