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What does the “__block” keyword mean?
What exactly does the __block keyword in Objective-C mean? I know it allows you to modify variables within blocks, but I'd like to know...
...
How to get name of exception that was caught in Python?
...rent ways to get the name of the class of the exception:
type(exception).__name__
exception.__class__.__name__
exception.__class__.__qualname__
e.g.,
try:
foo = bar
except Exception as exception:
assert type(exception).__name__ == 'NameError'
assert exception.__class__.__name__ == '...
Execution of Python code with -m option or not
....bar as the starting point.
Demo:
$ mkdir -p test/foo/bar
$ touch test/foo/__init__.py
$ touch test/foo/bar/__init__.py
$ cat << EOF > test/foo/bar/baz.py
> if __name__ == "__main__":
> print __package__
> print __name__
>
> EOF
$ PYTHONPATH=test python test/foo/bar...
Why is __dirname not defined in node REPL?
From the node manual I see that I can get the directory of a file with __dirname , but from the REPL this seems to be undefined. Is this a misunderstanding on my side or where is the error?
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Class with Object as a parameter
...
class Classic: pass
class NewStyle(object): pass
print(dir(Classic))
# ['__doc__', '__module__']
print(dir(NewStyle))
# ['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__',...
Approximate cost to access various caches and main memory?
...opy of a line. But remember, Intel uses MESIF (en.wikipedia.org/wiki/MESIF_protocol) for NUMA, AMD uses MOESI. I think within a single socket, though, MESIF isn't really a thing because data comes from L3, not core->core. So it's probably more relevant for L3 cache->cache transfers across s...
How do I get the full path of the current file's directory?
...3
For the directory of the script being run:
import pathlib
pathlib.Path(__file__).parent.absolute()
For the current working directory:
import pathlib
pathlib.Path().absolute()
Python 2 and 3
For the directory of the script being run:
import os
os.path.dirname(os.path.abspath(__file__))
I...
How to load all modules in a folder?
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List all python (.py) files in the current folder and put them as __all__ variable in __init__.py
from os.path import dirname, basename, isfile, join
import glob
modules = glob.glob(join(dirname(__file__), "*.py"))
__all__ = [ basename(f)[:-3] for f in modules if isfile(f) and not f.endswi...
C Macro definition to determine big endian or little endian machine?
...byte orders, ready to be put into a file called order32.h:
#ifndef ORDER32_H
#define ORDER32_H
#include <limits.h>
#include <stdint.h>
#if CHAR_BIT != 8
#error "unsupported char size"
#endif
enum
{
O32_LITTLE_ENDIAN = 0x03020100ul,
O32_BIG_ENDIAN = 0x00010203ul,
O32_PDP_E...
How to invoke the super constructor in Python?
...on-3.x the process has been simplified:
Python-2.x
class A(object):
def __init__(self):
print "world"
class B(A):
def __init__(self):
print "hello"
super(B, self).__init__()
Python-3.x
class A(object):
def __init__(self):
print("world")
class B(A):
def __init__(self):
print...