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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
...
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 ...
Which is faster: Stack allocation or Heap allocation
... on_stack doesn't do anything useful and can be optimized away. GCC on my Linux laptop also notices that on_heap doesn't do anything useful, and optimizes it away as well:
on_stack took 0.000003 seconds
on_heap took 0.000002 seconds
...
What version of javac built my jar?
...e or more classes from the jar. For example:
$ jar xf log4j-1.2.15.jar
On Linux, Mac OS X or Windows with Cygwin installed, the file(1) command knows the class version.
$ file ./org/apache/log4j/Appender.class
./org/apache/log4j/Appender.class: compiled Java class data, version 45.3
Or alternative...
How to view revision history for Mercurial file?
... very nice! but 'hgtk' is now only a wrapper, please use 'thg' on linux
– milkplus
Dec 11 '11 at 18:32
...
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.
...
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...
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...
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
...
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...