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Does Foreign Key improve query performance?
...n FK does not create an associated index, and you should create indexes on all FK fields to improve look up times.
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How to test equality of Swift enums with associated values
...d values.
So if you're on Swift 4.1 or newer, the following will automatically synthesize the necessary methods such that XCTAssert(t1 == t2) works. The key is to add the Equatable protocol to your enum.
enum SimpleToken: Equatable {
case Name(String)
case Number(Int)
}
let t1 = SimpleToke...
How would I create a UIAlertView in Swift?
... the handler might need to pass the chosen title off to some other method call
– Honey
Nov 30 '16 at 17:27
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Python: Checking if a 'Dictionary' is empty doesn't seem to work
...; not dct
True
>>>
Thus, your isEmpty function is unnecessary. All you need to do is:
def onMessage(self, socket, message):
if not self.users:
socket.send("Nobody is online, please use REGISTER command" \
" in order to register into the server")
else:...
Downloading a file from spring controllers
...
@RequestMapping(value = "/files/{file_name}", method = RequestMethod.GET)
public void getFile(
@PathVariable("file_name") String fileName,
HttpServletResponse response) {
try {
// get your file as InputStream
InputStream is = ...;
...
Call ASP.NET function from JavaScript?
... Page.ClientID %>';
__doPostBack(pageId, argumentString);
This will call the 'RaisePostBackEvent' method in your code file with the 'eventArgument' as the 'argumentString' you passed from the JavaScript. Now, you can call any other event you like.
P.S: That is 'underscore-underscore-doPostBac...
What are the differences between struct and class in C++?
...
That's not really a second difference, it's just that the question stated the difference incompletely. All subobjects are private by default when using the class, public by default with struct, and both define a class type.
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What is the preferred syntax for defining enums in JavaScript?
...
This isn't much of an answer, but I'd say that works just fine, personally
Having said that, since it doesn't matter what the values are (you've used 0, 1, 2), I'd use a meaningful string in case you ever wanted to output the current value.
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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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How to identify if the DLL is Debug or Release build (in .NET) [duplicate]
...s to check the compiled assemblies itself. There is this very useful tool called '.NET Assembly Information' found here by Rotem Bloom. After you install this, it associates itself with .dll files to open with itself. After installing you can just double-click on the Assembly to open and it will giv...