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Does ARC support dispatch queues?
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The short answer: YES, ARC retains and releases dispatch queues.
And now for the long answer…
If your deployment target is lower than iOS 6.0 or Mac OS X 10.8
You need to use dispatch_retain and dispatch_release on your queue. ARC does not manage ...
How can I generate random alphanumeric strings?
How can I generate a random 8 character alphanumeric string in C#?
33 Answers
33
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Advantages of std::for_each over for loop
...h only seems to hinder the readability of code. Why do then some coding standards recommend its use?
21 Answers
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postgresql - replace all instances of a string within text field
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Hi guys, I like your answer and explanation, it is really helpful. Could you please add an example using regexp_replace? Thanks!
– Wim Feijen
Oct 22 '14 at 16:09
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What's the difference between Task.Start/Wait and Async/Await?
...g something
You are.
what is the difference between doing Task.Wait and await task?
You order your lunch from the waiter at the restaurant. A moment after giving your order, a friend walks in and sits down next to you and starts a conversation. Now you have two choices. You can ignore your ...
xtreme toolkit pro——CXTPReportControl控件教程 - C/C++ - 清泛网 - 专注C/C++及内核技术
...自定义控件，将该控件的class属性改为XTPReport，ID改为;IDC_REPORTCTRL_LIST。
（2）添加一个自定义变量：CXTPReportControl m_wndReportCtrl;
（3）将控件和变量联系起来，在对话框初始化函数OnInitDialog()中添加如下代码：
m_wndReportCtrlList.Sub...
Get time difference between two dates in seconds
...he explanation
You need to call the getTime() method for the Date objects, and then simply subtract them and divide by 1000 (since it's originally in milliseconds). As an extra, when you're calling the getDate() method, you're in fact getting the day of the month as an integer between 1 and 31 (not ...
Setting different color for each series in scatter plot on matplotlib
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I don't know what you mean by 'manually'. You can choose a colourmap and make a colour array easily enough:
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.cm as cm
x = np.arange(10)
ys = [i+x+(i*x)**2 for i in range(10)]
colors = cm.rainbow(np.linspace(0, 1, len(ys)))
f...
SQLite - UPSERT *not* INSERT or REPLACE
...no-op if the INSERT would violate a uniqueness constraint. UPSERT is not standard SQL. UPSERT in SQLite follows the syntax established by PostgreSQL.
GOOD but tendous: This will update 2 of the columns.
When ID=1 exists, the NAME will be unaffected.
When ID=1 does not exist, the name will be the...
What is process.env.PORT in Node.js?
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In many environments (e.g. Heroku), and as a convention, you can set the environment variable PORT to tell your web server what port to listen on.
So process.env.PORT || 3000 means: whatever is in the environment variable PORT, or 3000 if there's nothing there...