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How do I test for an empty JavaScript object?
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// because Object.keys(new Date()).length === 0;
// we have to do some additional check
Object.keys(obj).length === 0 && obj.constructor === Object
Note, though, that this creates an unnecessary array (the return value of keys).
Pre-ECMA 5:
function isEmpty(obj) {
for(var prop in obj)...
Why isn't String.Empty a constant?
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The reason that static readonly is used instead of const is due to use with unmanaged code, as indicated by Microsoft here in the Shared Source Common Language Infrastructure 2.0 Release. The file to look at is sscli20\clr\src\bcl\system\string.cs.
The Empty constant holds the empty
string ...
What are the respective advantages/limitations of Amazon RDS vs. EC2 with MySQL? [closed]
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This is a simple question with a very complicated answer!
In short: EC2 will provide maximum performance if you go with a RAID0 EBS. Doing RAID0 EBS requires a pretty significant amount of maintenance overhead, for example:
http://alestic.com/2009/06...
What is an Intent in Android?
... to happen. Depending on the intent, apps or the OS might be listening for it and will react accordingly. Think of it as a blast email to a bunch of friends, in which you tell your friend John to do something, or to friends who can do X ("intent filters"), to do X. The other folks will ignore the em...
private final static attribute vs private final attribute
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In general, static means "associated with the type itself, rather than an instance of the type."
That means you can reference a static variable without having ever created an instances of the type, and any code referring to the variable is referring to the exact...
Exception thrown in NSOrderedSet generated accessors
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I reproduced your setup both with your data model and one of my own with different names. I got the same error in both cases.
Looks like a bug in Apple's autogenerated code.
sh...
What is a singleton in C#?
What is a Singleton and when should I use it?
16 Answers
16
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Selecting the last value of a column
I have a spreadsheet with some values in column G. Some cells are empty in between, and I need to get the last value from that column into another cell.
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What is the purpose of “android.intent.category.DEFAULT”?
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Categories are used for implicit Intents. So, If your Activity can be started by an implicit Intent when no other specific category is assigned to activity, activity's Intent filter should include this category. (even if you have other categories in the I...
Does Spring @Transactional attribute work on a private method?
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The Question is not private or public, the question is: How is it invoked and which AOP implementation you use!
If you use (default) Spring Proxy AOP, then all AOP functionality provided by Spring (like @Transactional) will only be taken into account if the call goes through the proxy. -...