|
- What is _: in Swift telling me? - Stack Overflow
[The Swift 2 0 spec is important here In Swift 2 0, the first param name is always not externalized by default, and the other param names are externalized by default In Swift 1 2 and before, the externalization rules depended on where the declaration appeared, which was unnecessarily inconsistent and confusing ]
- 国际结算系统 SWIFT 是什么？ - 知乎
swift的角色是制定跨境清算信息的标准，并向相关机构进行传递，而不是直接从事清算或者结算的机构。也就是说swift不对银行账户做任何划拨，对银行账户进行资金划拨的是清算业务和结算业务，这在不同的国家由不同的系统来完成。
- swift - What is the difference between a weak reference and an unowned . . .
Similarly swift maintains unowned reference count and weak reference counts for the object (weak reference points to something called a "side table" rather than the object itself ) When the strong reference count reaches zero, the object gets deinitialised, but it cannot be deallocated if the unowned reference count is more than zero
- What is the difference between `let` and `var` in Swift?
Swift let vs var let - constant var - variable [Constant vs variable] [Struct vs Class] Official doc docs swift org says The value of a constant can’t be changed once it’s set, whereas a variable can be set to a different value in the future This terminology actually describes a reassign mechanism Mutability
- How to serialize or convert Swift objects to JSON?
UPDATE: Codable protocol introduced in Swift 4 should be sufficient for most of the JSON parsing cases Below answer is for people who are stuck in previous versions of Swift and for legacy reasons EVReflection: This works of reflection principle This takes less code and also supports NSDictionary, NSCoding, Printable, Hashable and Equatable
- How do I concatenate or merge arrays in Swift? - Stack Overflow
Swift provides a joined() method for all types that conform to Sequence protocol (including Array) joined() has the following declaration: Returns the elements of this sequence of sequences, concatenated func joined() -> FlattenSequence<Self> Besides, Swift Array has a init(_:) initializer init(_:) has the following declaration:
- Get Unix Epoch Time in Swift - Stack Overflow
Swift's timeIntervalSince1970 returns seconds with what's documented as "sub-millisecond" precision, which I've observed to mean usually microseconds but sometimes one scale (one digit to the right of the decimal) less or more When it returns a scale of 5 (5 digits after the decimal), I assume Swift couldn't produce 6 scales of precision, and
- option type - What is an optional value in Swift? - Stack Overflow
An optional in Swift is a type that can hold either a value or no value Optionals are written by appending a ? to any type: var name: String? = "Bertie" Optionals (along with Generics) are one of the most difficult Swift concepts to understand Because of how they are written and used, it's easy to get a wrong idea of what they are
|
|
|