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typeof !== “undefined” vs. != null
...gument, or as a global variable), I think the best way to do it is:
if (my_variable === undefined)
jQuery does it, so it's good enough for me :-)
Otherwise, you'll have to use typeof to avoid a ReferenceError.
If you expect undefined to be redefined, you could wrap your code like this:
(functi...
How to get Maven project version to the bash command line
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I'm removing all logging (INFO,WARNING,etc) and 'Download' messages with mvn org.apache.maven.plugins:maven-help-plugin:2.1.1:evaluate -Dexpression=project.version|grep -Ev '(^\[|Download\w+:)'
– Chadwick
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What are all the common undefined behaviours that a C++ programmer should know about? [closed]
What are all the common undefined behaviours that a C++ programmer should know about?
11 Answers
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Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
...able of a class with the mutable keyword. As far as I can see it simply allows you to modify a variable in a const method:
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服务器保持大量TIME_WAIT和CLOSE_WAIT的解决方法 - C/C++ - 清泛网 - 专注C/C++及内核技术
服务器保持大量TIME_WAIT和CLOSE_WAIT的解决方法昨天解决了一个HttpClient调用错误导致的服务器异常，具体过程如下：http: blog.csdn.net shootyou article details 6615051里头的分析过...昨天解决了一个HttpClient调用错误导致的服务器异常，具体...
View a list of recent documents in Vim
...@Stew link to that question? Those don't seem to work for me. [UPDATE] actually it works for me with :browse oldfiles – sorry!
– Aaron Gibralter
Feb 20 '14 at 6:11
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How can I load storyboard programmatically from class?
... xib . But I can't find proper way to load and show storyboard programmatically. Project was started developing with xib, and now it's very hard to nest all xib files in storyboard. So I was looking a way to do it in code, like with alloc, init, push for viewControllers. In my case I have only one...
What is the Swift equivalent of respondsToSelector?
...e are multiple candidates: let theMethod = delegate.userNotificationCenter(_:willPresent:withCompletionHandler:)
– Cœur
May 4 '18 at 8:47
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How to dynamically update a ListView on Android [closed]
...lns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<!-- Pretty hint text, and maxLines -->
<EditText android:id="@+building_list/search_box"
android...
What are the advantages of using a schema-free database like MongoDB compared to a relational databa
...ire several tables to properly represent in a relational db. This is especially useful if your data is immutable.
Deep query-ability. MongoDB supports dynamic queries on documents using a document-based query language that's nearly as powerful as SQL.
No schema migrations. Since MongoDB is schema-...