所有默认函数在 Swift 名字空间,即 Swift.abs 这样。

所有的函数功能都是我猜的。猜错别找我。

第一部分 a to z

abs

abs(x: T) -> T

绝对值, 所有数字类型均可。

abs(-20.3)

advance

advance(start: T, n: T.DistanceType) -> T
advance(start: T, n: T.DistanceType, end: T) -> T

计算步进和距离的函数貌似。

advance(0, 20) // 20
advance(2, 20, 4) // 4

alignof alignofValue

alignof(T.Type) -> Int
alignofValue(T) -> Int

计算类型的 alignment。

alignof(Int)
alignof(Uint8)
alignofValue(Float(3.2))

assert

assert(condition: @auto_closure () -> Bool, message: StaticString, file: StaticString, line: UWord) -> Void
assert(condition: @auto_closure () -> T, message: StaticString, file: StaticString, line: UWord) -> Void

断言语句。因为是 @auto_closure, 所以直接写语句就可以了,第二个 T 的限制是 LogicValue, 所以 Optional 也可以。

let age = 17
assert(age > 0, "Alive Only")
assert(age > 18, "Adult Only", file: __FILE__, line: __LINE__)
assert("342345".toInt())

bridge*

bridgeFromObjectiveC(x: AnyObject, T.Type) -> T?
bridgeFromObjectiveCUnconditional(x: AnyObject, T.Type) -> T
bridgeToObjectiveC(x: T) -> AnyObject?
bridgeToObjectiveCUnconditional(x: T) -> AnyObject

c_malloc_size

c_malloc_size(heapMemory: UnsafePointer<Void>) -> Int

c_memcpy

c_memcpy(dest: UnsafePointer<Void>, src: UnsafePointer<Void>, size: UInt) -> Void

c_putchar(value: Int32) -> Void

c_putchar(value: Int32) -> Void

就是 putchar,最基础的 output 语句。

c_putchar(97) // ASCII 'a'

contains

contains(seq: S, predicate: (S.GeneratorType.Element) -> L) -> Bool
contains(seq: S, x: S.GeneratorType.Element) -> Bool

判断序列是否包含某元素、是否包含满足某条件的元素。

let a = [1,2,4,56,7]
contains(a, { $0 > 50 }) // true
contains(a, 56)

count countElements

count(r: Range<I>) -> I.DistanceType
countElements(x: T) -> T.IndexType.DistanceType

数元素、Range 个数。

count(1..20)
let a = [1,2,4,56,7]
countElements(a) // 5

countLeadingZeros

countLeadingZeros(value: Int64) -> Int64

Count Leading Zeros in Binary Format. 二进制格式前面有多少个 0.

countLeadingZeros(1) // 63
countLeadingZeros(-1) // 0

debugPrint debugPrintln

debugPrint(object: T) -> Void
debugPrint(object: T, &target: TargetStream) -> Void
debugPrintln(object: T) -> Void
debugPrintln(object: T, &target: TargetStream) -> Void

打印任意对象。TargetStream 暂时未知。

distance

distance(start: T, end: T) -> T.DistanceType

起止距离.

distance(1, 20) // 19

dropFirst dropLast

dropFirst(seq: Seq) -> Seq.SliceType
dropLast(seq: Seq) -> Seq.SliceType

序列操作函数。

let b = [1,2,3,4,5]
// b : Array<Int> = [1, 2, 3, 4, 5]
dropFirst(b)
// r16 : Slice<Int> = [2, 3, 4, 5]
dropLast(b)
// r17 : Slice<Int> = [1, 2, 3, 4]

dump

dump(x: T, name: String?, indent: Int, maxDepth: Int, maxItems: Int) -> T
dump(x: T, name: String?, indent: Int, maxDepth: Int, maxItems: Int, &targetStream: TargetStream) -> T

打印变量的详情。

let b = [1,2,3,4,5]
dump(b) // detailed output at console
dump(b, name: "A Array B")
dump("Hello World")

encodeBitsAsWords

encodeBitsAsWords(x: T) -> Word[]

未知作用。尝试发现类型是 ASCII 码。

encodeBitsAsWords(97) // [97]: Word[]

enumerate

enumerate(seq: Seq) -> EnumerateGenerator<Seq.GeneratorType>

同 Python enumerate.

let b = [1,2,3,4,5]
for (idx, val) in enumerate(b) { println("b \(idx) = \(val)") }

equal

equal(a1: S1, a2: S2) -> Bool
equal(a1: S1, a2: S2, pred: (S1.GeneratorType.Element, S1.GeneratorType.Element) -> Bool) -> Bool

比较相等。

equal(2, 1+1)
equal([1,2,3,4], [2,4,6,8], { $0 * 2 == $1 })

fatalError

fatalError(message: StaticString, file: StaticString, line: UWord) -> Void

Runtime fatal error. then quit.

fatalError("Taylor Swift Sucks")

filter

filter(source: C, includeElement: (C.GeneratorType.Element) -> Bool) -> FilterCollectionView<C>
filter(source: S, includeElement: (S.GeneratorType.Element) -> Bool) -> FilterSequenceView<S>

同 Python filter。

let b = [1,2,3,4,5]
for i in filter(b, { $0 > 3 }) { println("got \(i)") }
for i in filter(1...100, { $0 % 17 == 0 }) { println("got \(i)") }

find

find(domain: C, value: C.GeneratorType.Element) -> C.IndexType?

查找某一元素的索引值。

let b = [1,2,3,4,5]
find(b, 20) // nil
find(b, 2)  // 1

getBridgedObjectiveCType

getBridgedObjectiveCType(T.Type) -> Any.Type?

getVaList

getVaList(args: CVarArg[]) -> CVaListPointer

indices

indices(seq: Seq) -> Range<Seq.IndexType>

索引的迭代器。

let b = [1,2,3,4,5]
for i in indices(b) { println(i) }
// 0 1 2 3 4

insertionSort

insertionSort(&elements: C, range: Range<C.IndexType>) -> Void
insertionSort(&elements: C, range: Range<C.IndexType>, &less: (C.GeneratorType.Element, C.GeneratorType.Element) -> Bool) -> Void

插入排序。range 表示排序范围。

var tt = [23, 34, 56, 45, 67, 12, 78, 89, 90]
insertionSort(&tt, 0..5)
println(tt)

isBridgedToObjectiveC isBridgedVerbatimToObjectiveC

isBridgedToObjectiveC(T.Type) -> Bool
isBridgedVerbatimToObjectiveC(T.Type) -> Bool

isUniquelyReferenced

isUniquelyReferenced(&x: T) -> Bool

join

func join<C : ExtensibleCollection, S : Sequence where C == C>(separator: C, elements: S) -> C

序列的 join 操作

join("!!", ["Hello", "World"])

lexicographicalCompare

lexicographicalCompare(a1: S1, a2: S2) -> Bool
lexicographicalCompare(a1: S1, a2: S2, less: (S1.GeneratorType.Element, S1.GeneratorType.Element) -> Bool) -> Bool

map

map(source: C, transform: (C.GeneratorType.Element) -> T) -> MapCollectionView<C, T>
map(source: S, transform: (S.GeneratorType.Element) -> T) -> MapSequenceView<S, T>
map(x: T?, f: (T) -> U) -> U?

同 Python map 操作。

for i in map([1,2,3,4], { $0 * 10 }) { println(i) }
let optVal: Int? = 250
let v: Int? =  map(optVal, { $0 + 1 }) // 251

max maxElement

max(x: T, y: T, rest: T[]) -> T
maxElement(range: R) -> R.GeneratorType.Element

最大值。

max(2, 4)
max(1,2,4,5,6,100,4,5,6,7) // 100
maxElement([1,2,4,5,6,100,4,5,6,7])

min minElement

min(x: T, y: T, rest: T[]) -> T
minElement(range: R) -> R.GeneratorType.Element

最小值。Same usage as max

numericCast

numericCast(x: T) -> U

Cast between unsigned and signed integers.

let bb: UInt8 = 20
let cc: Int = numericCast(bb)

partition

partition(&elements: C, range: Range<C.IndexType>) -> C.IndexType
partition(&elements: C, range: Range<C.IndexType>, &less: (C.GeneratorType.Element, C.GeneratorType.Element) -> Bool) -> C.IndexType

Unknown usage.

var tt = [12, 23, 34, 45, 56, 67, 78, 89, 90]
println(partition(&tt, 3..4))

posix_read posix_write

posix_read(fd: Int32, buf: RawPointer, sz: Int) -> Int
posix_write(fd: Int32, buf: RawPointer, sz: Int) -> Int
print(object: T) -> Void
print(object: T, &target: TargetStream) -> Void
println() -> Void
println(object: T) -> Void
println(object: T, &target: TargetStream) -> Void

打印语句,们。

quickSort

quickSort(&elements: C, range: Range<C.IndexType>) -> Void
quickSort(&elements: C, range: Range<C.IndexType>, less: (C.GeneratorType.Element, C.GeneratorType.Element) -> Bool) -> Void

快排序, range表示需要排序的范围。

var tt = [23, 34, 56, 45, 67, 12, 78, 89, 90]
quickSort(&tt, 0..5)
quickSort(&tt, 0..5, { $1 < $0 }) // 逆序

reduce

reduce(sequence: S, initial: U, combine: (U, S.GeneratorType.Element) -> U) -> U

同 Python 中 reduce, 类似 Haskell fold 系列函数。

// reduce 应用之 求和
let tt = [23, 34, 56, 45, 67, 12, 78, 89, 90]
reduce(tt, 0, { $0 + $1 })

reflect

reflect(x: T) -> Mirror

暂时未知

reinterpretCast

reinterpretCast(x: T) -> U

相同 size 的类型,之间的直接 cast.

let a: Int = -1
let c: UInt = reinterpretCast(a)
println(c)
println(UInt.max) // 一定等于 c 。别问我为什么。

reverse

reverse(source: C) -> ReverseView<C>

同 Python reversed(),逆序的迭代器。

let tt = [23, 34, 56, 45, 67, 12, 78, 89, 90]
for i in reverse(tt) { println(i) }

roundUpToAlignment

roundUpToAlignment(offset: Int, alignment: Int) -> Int

内存 alignment 计算函数。比如 alignment 为 4 字节,offset 为 5, 那么将在下个 4 字节, 即 8 的位置上对齐。

roundUpToAlignment(2, 4) // 4
roundUpToAlignment(5, 4) // 8

sizeof sizeofValue

sizeof(T.Type) -> Int
sizeofValue(T) -> Int

计算类型或者值的 size。

sizeof(Int)
sizeofValue(2.4)  // a Double

sort

sort(array: T[]) -> T[]
sort(array: T[], pred: (T, T) -> Bool) -> T[]

排序函数。类似 Python sorted()。

let foo = [18, 14, 21, 8, 45, 12, 9]
sort(foo)
sort(foo, { String($0) < String($1) }) // 按照 ASCII 顺序排序

split

split(seq: Seq, isSeparator: (Seq.GeneratorType.Element) -> R, maxSplit: Int, allowEmptySlices: Bool) -> Seq.SliceType[]

分割序列函数。

split("Hello World", { $0 == " " })
// : String[] = ["Hello", "World"]

startsWith

startsWith(s0: S0, s1: S1) -> Bool

判断序列开头子序列。

startsWith(1..100, 1..2)
startsWith("Hello World", "Hel")

strideof strideofValue

strideof(T.Type) -> Int
strideofValue(T) -> Int

计算内存 stride 。用法同 sizeof sizeofValue。

swap

swap(&a: T, &b: T) -> Void

交换值。

var a = 1, b = 2
swap(&a, &b)

swift_*

swift_bufferAllocate(bufferType: HeapBufferStorageBase.Type, size: Int, alignMask: Int) -> AnyObject
swift_keepAlive(&T) -> Void
swift_MagicMirrorData_summaryImpl(metadata: Any.Type, result: UnsafePointer<String>) -> Void

toString

toString(object: T) -> String

这个没啥好说的。就是 toString。例子我都懒得举。

transcode

transcode(inputEncoding: Encoding.Type, outputEncoding: Encoding.Type, input: Input, output: Output) -> Void
transcode(inputEncoding: InputEncoding.Type, outputEncoding: OutputEncoding.Type, input: Input, output: Output) -> Void

未知。

underestimateCount

underestimateCount(x: T) -> Int

预估 Sequence 的成员个数。

underestimateCount(1..1000)

unsafeReflect

unsafeReflect(owner: NativeObject, ptr: UnsafePointer<T>) -> Mirror

未知。

withExtendedLifetime

withExtendedLifetime(x: T, f: (T) -> Result) -> Result

withObjectAtPlusZero

withObjectAtPlusZero(x: AnyObject, f: (COpaquePointer) -> Result) -> Result

withUnsafePointer withUnsafePointers withUnsafePointerToObject

withUnsafePointer(&arg: T, body: (UnsafePointer<T>) -> Result) -> Result
withUnsafePointers(&arg0: A0, &arg1: A1, &arg2: A2, body: (UnsafePointer<A0>, UnsafePointer<A1>, UnsafePointer<A2>) -> Result) -> Result
withUnsafePointers(&arg0: A0, &arg1: A1, body: (UnsafePointer<A0>, UnsafePointer<A1>) -> Result) -> Result
withUnsafePointerToObject(&arg: T?, body: (UnsafePointer<ImplicitlyUnwrappedOptional<T>>) -> Result) -> Result

来自 Rust 的同学对这里一定不会太陌生。不过作用和使用场合未知。

withVaList

withVaList(args: CVarArg[], f: (CVaListPointer) -> R) -> R
withVaList(builder: VaListBuilder, f: (CVaListPointer) -> R) -> R