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What is the purpose of willSet and didSet in Swift?
...seems to be that sometimes, you need a property that has automatic storage and some behavior, for instance to notify other objects that the property just changed. When all you have is get/set, you need another field to hold the value. With willSet and didSet, you can take action when the value is mo...
Format Instant to String
...-zone is required. Without a time-zone, the formatter does not know how to convert the instant to human date-time fields, and therefore throws an exception.
The time-zone can be added directly to the formatter using withZone().
DateTimeFormatter formatter =
DateTimeFormatter.ofLocalizedDateTim...
Access an arbitrary element in a dictionary in Python
...ction() results do not support indexing, this is why first of all we must convert it into a list and then we can use the index [0]
– Noki
May 24 '19 at 9:41
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What are some uses of decltype(auto)?
... uses
You can also use decltype(auto) in other contexts, e.g. the draft Standard N3936 also states
7.1.6.4 auto specifier [dcl.spec.auto]
1 The auto and decltype(auto) type-specifiers designate a placeholder
type that will be replaced later, either by deduction from an
initializer or by ...
How to check for file lock? [duplicate]
...
No, unfortunately, and if you think about it, that information would be worthless anyway since the file could become locked the very next second (read: short timespan).
Why specifically do you need to know if the file is locked anyway? Knowing...
Programmatically obtain the Android API level of a device?
...ION.SDK_INT >= Build.VERSION_CODES.DONUT) {
}
To obtain user visible Android Version use:
Build.VERSION.RELEASE
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“static const” vs “#define” vs “enum”
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It depends on what you need the value for. You (and everyone else so far) omitted the third alternative:
static const int var = 5;
#define var 5
enum { var = 5 };
Ignoring issues about the choice of name, then:
If you need to pass a pointer around, you must use (1).
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Pointer to pointer clarification
...are doing is *ipp get the object at the address held in ipp which is ip1 and then assign to ip1 the value stored in ip2, which is the address of j.
Simply
& --> Address of
* --> Value at
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How to update the value stored in Dictionary in C#?
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Just point to the dictionary at given key and assign a new value:
myDictionary[myKey] = myNewValue;
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What are the rules for calling the superclass constructor?
...bar
}
};
More info on the constructor's initialization list here and here.
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