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Python: most idiomatic way to convert None to empty string?
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If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
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Will the Garbage Collector call IDisposable.Dispose for me?
...lizer, and implement IDisposable, that your finalizer needs to explicitly call Dispose.
This is logical, and is what I've always done in the rare situations where a finalizer is warranted.
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Can you run GUI applications in a Docker container?
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You can simply install a vncserver along with Firefox :)
I pushed an image, vnc/firefox, here: docker pull creack/firefox-vnc
The image has been made with this Dockerfile:
# Firefox over VNC
#
# VERSION 0.1
# DOCKER-VERSION ...
'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
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and tests whether both expressions are logically True while & (when used with True/False values) tests if both are True.
In Python, empty built-in objects are typically treated as logically False while non-empty built-ins are logically True. This facilitates the c...
Markup XML解析库下载（Markup.h 和 Markup.cpp） - 源码下载 - 清泛网 - 专注C/C++及内核技术
... Markup Release 11.1
// Copyright (C) 2009 First Objective Software, Inc. All rights reserved
// Go to www.firstobject.com for the latest CMarkup and EDOM documentation
// Use in commercial applications requires written permission
// This software is provided "as is", with no warranty.
#if !d...
Two way/reverse map [duplicate]
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1
>>> del d['foo']
>>> d['bar']
Traceback (most recent call last):
File "<stdin>", line 7, in <module>
KeyError: 'bar'
I'm sure I didn't cover all the cases, but that should get you started.
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How to Calculate Execution Time of a Code Snippet in C++
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You can use this function I wrote. You call GetTimeMs64(), and it returns the number of milliseconds elapsed since the unix epoch using the system clock - the just like time(NULL), except in milliseconds.
It works on both windows and linux; it is thread safe.
Not...
Python list subtraction operation
... [1,2] you will get empty list. [1,1,2,2] - [2] gives [1,1] So it is not really list substraction, it is more like "List from List X without elements from set Y".
– Alfred Zien
Feb 6 '16 at 10:25
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What is the difference between “px”, “dip”, “dp” and “sp”?
...lems with dp while everything works fine with dip
– DallaRosa
Jul 4 '11 at 6:07
255
One note abou...
How to determine CPU and memory consumption from inside a process?
... quite a while, perhaps I've been only a bit stupid...)
Note: for clarity all error checking has been omitted from the following code. Do check the return codes...!
Total Virtual Memory:
#include "windows.h"
MEMORYSTATUSEX memInfo;
memInfo.dwLength = sizeof(MEMORYSTATUSEX);
GlobalMemoryStatus...