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Memoizer

Memoizer is a struct, that can be used to calculate different recursive functions with repeatingly the same values.

To do that it saves every single calculated result in a Dictionary and can then, if repeatedly called, just take a already calcualted result from the dictionnary instead of recalculating it.

Use cases

Fibonacci numbers, factorial, see MemoizerExamples.swift

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Atomic

var myAtomic = Atomic<Int>(5)
myAtomic.synced { $0 = 2 }
print( myAtomic.value )
// Prints "2"

Atomic is a generic wrapper-struct for values that need to be accessible safely, when working concurrently.

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CatchLoop

The function can be used to iterate over a sequence (implementing Sequence-protocol).

It returns a dictionary containing either the returned value or a thrown error.

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String subscripts

Implementation of string subscripts using Int.

var str = "😂😅😊😜😝"
str[0..<2] = ""
print(str)
// Prints "😊😜😝"

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Dijkstra

Swift implementation of Dijkstra's graph algorithm to find the shortest path between two vertices.

see https://en.wikipedia.org/wiki/Dijkstra%27s_algorithm

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Numeric

Numeric is a protocol which unites numeric values.

inherited operators

!=, ==, <, >, <=, >=

+, -, *, /, %

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Constants

constant values

pi, tau, e, y_0, h, c

often used sets

Z(_: Int) for sets of integer up to (excluding) a given number.

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Modelling group-like algebraic structures

Magma

Requirements: The given operation is closed under the given set.

Semigroup

Requirements: is a Magma, operation is associative. (a • b) • c == a • (b • c)

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String manipulation operators

let fiveTimesHello = 5 * "hello" // "hellohellohellohellohello"
let helloPlus5 = "hello" + 5 // "hello5"

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Bool extensions

Comparable