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What is an “unwrapped value” in Swift?
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cantBeNil = nil // can't do this
To get the value from your variable if it is optional, you have to unwrap it. This just means putting an exclamation point at the end.
var canBeNil : Int? = 4
println(canBeNil!)
Your code should look like this:
let optionalSquare: Square? = Square(sideLength: ...
What's the best way to refactor a method that has too many (6+) parameters?
Occasionally I come across methods with an uncomfortable number of parameters. More often than not, they seem to be constructors. It seems like there ought to be a better way, but I can't see what it is.
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How can I check if an element exists in the visible DOM?
How do you test an element for existence without the use of the getElementById method?
25 Answers
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What are the benefits to marking a field as `readonly` in C#?
What are the benefits of having a member variable declared as read only? Is it just protecting against someone changing its value during the lifecycle of the class or does using this keyword result in any speed or efficiency improvements?
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Is it possible to run JavaFX applications on iOS, Android or Windows Phone 8?
Can one develop an entire application using JavaFX and run it on iOS, Android or Windows Phone 8, without writing platform-specific code?
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How to use LocalBroadcastManager?
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I'll answer this anyway. Just in case someone needs it.
ReceiverActivity.java
An activity that watches for notifications for the event named "custom-event-name".
@Override
public void onCreate(Bundle savedInstanceState) {
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// Register to receive messages.
// We ...
How does the “this” keyword work?
...n't appear to be a clear explanation of what the this keyword is and how it is correctly (and incorrectly) used in JavaScript on the Stack Overflow site.
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Accessing constructor of an anonymous class
...I have a concrete class Class1 and I am creating an anonymous class out of it.
10 Answers
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Why are hexadecimal numbers prefixed with 0x?
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Short story: The 0 tells the parser it's dealing with a constant (and not an identifier/reserved word). Something is still needed to specify the number base: the x is an arbitrary choice.
Long story: In the 60's, the prevalent programming number systems were d...
How do I find the length of an array?
...f(a)/sizeof(*a)) << std::endl;
This doesn't work on pointers (i.e. it won't work for either of the following):
int *p = new int[7];
std::cout << "Length of array = " << (sizeof(p)/sizeof(*p)) << std::endl;
or:
void func(int *p)
{
std::cout << "Length of array ...