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How can I check for “undefined” in JavaScript? [duplicate]
...terested in finding out whether a variable has been declared regardless of its value, then using the in operator is the safest way to go. Consider this example:
// global scope
var theFu; // theFu has been declared, but its value is undefined
typeof theFu; // "undefined"
But this may not be the i...
Which @NotNull Java annotation should I use?
...nar) to avoid NullPointerExceptions. Many of the tools seem incompatible with each others' @NotNull / @NonNull / @Nonnull annotation and listing all of them in my code would be terrible to read. Any suggestions of which one is the 'best'? Here is the list of equivalent annotations I've found:
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Git SSH error: “Connect to host: Bad file number”
I followed the git guide but I have this strange issue when trying to connect to github:
19 Answers
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How do I convert a String object into a Hash object?
... by calling Hash#inspect can be turned back into a hash by calling eval on it. However, this requires the same to be true of all of the objects in the hash.
If I start with the hash {:a => Object.new}, then its string representation is "{:a=>#<Object:0x7f66b65cf4d0>}", and I can't use e...
What is dynamic programming? [closed]
...Dynamic programming is used a lot in string problems, such as the string edit problem. You solve a subset(s) of the problem and then use that information to solve the more difficult original problem.
With dynamic programming, you store your results in some sort of table generally. When you need the...
Pick a random value from an enum?
...follow
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edited Dec 29 '09 at 1:02
answered Dec 29 '09 at 0:56
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JS: iterating over result of getElementsByClassName using Array.forEach
I want to iterate over some DOM elements, I'm doing this:
11 Answers
11
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ASP.NET Identity - HttpContext has no extension method for GetOwinContext
I have downloaded, and successfully ran the ASP.NET Identity sample from here:
https://github.com/rustd/AspnetIdentitySample
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Is an empty href valid?
... string may be a URI reference.
HTML 4.01
HTML 4.01 uses RFC 2396, where it says in section 4.2. Same-document References (bold emphasis mine):
A URI reference that does not contain a URI is a reference to the current document. In other words, an empty URI reference within a document is inter...
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...
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