LucianoPAlmeida

//
//  main.swift
//  InterspesedSequence
//
//  Created by Luciano Almeida on 19/01/19.
//  Copyright © 2019 Luciano Almeida. All rights reserved.
//


/// A lazy view for sequence that creates a new sequece where for each iteration of the base sequence the value is inserted.

LucianoPAlmeida

struct HTTPResponse {
    var statusCode: Int
}

extension HTTPResponse {
    func validateStatus<R>(in range: R) -> Bool where R: RangeExpression, R.Bound == Int {
        return range~=self.statusCode
    }
}

LucianoPAlmeida

//
//  RotatedCollection.swift
//  Collections
//
//  Created by Luciano Almeida on 10/02/19.
//  Copyright © 2019 Luciano Almeida. All rights reserved.
//

@_fixed_layout
public struct RotatedCollection<Base: Collection> {

LucianoPAlmeida

import Foundation

struct P {
    var b: Bool
    var i: Int
}

MemoryLayout<P>.size       // returns 9
MemoryLayout<P>.alignment  // returns 8
MemoryLayout<P>.stride     // returns 16

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@_fixed_layout
public struct RotatedCollection<Base: Collection> {
    @usableFromInline
    internal let _base: Base
    @usableFromInline
    internal let _offset: Int
    @usableFromInline
    internal let _computedOffset: Int
    
    /// Complexity: O(1) only when `Base` conforms to ramdom access collection.

LucianoPAlmeida

import Foundation

final class AtomicBool: CustomStringConvertible  {
    
    private var _value = _stdlib_AtomicInt(0)
    
    public init(_ value: Bool) {
        self._value.store(asInt(value))
    }

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let array = [1, 2, 3, 4, 5]

let r1: [Int] = array.reversed() // Eager reverse implementation is O(n) when call the function
let r2: ReversedCollection<[Int]> = array.reversed() // Lazy reversed collection is O(1) when you call the method.

r1.first { $0 == 3 } // Interate 3 times + O(n) complexity of eager call.
r2.first { $0 == 3 } // Interate 3 times + O(1) of lazy call. For a large array, this is an example where using a lazy type is more performant than an eager one.

LucianoPAlmeida

// Example of creating a Any keyword.
SyntaxFactory.makeAnyKeyword() 

// Example of creating a declaration modifier with a details also create with SyntaxFactory.
SyntaxFactory.makeBlankDeclModifier().withDetail(
            SyntaxFactory.makeUnknown("").withLeadingTrivia(trivia)
)

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// This will create a new DeclModifierSyntax with the same information that 
// makeBlankDeclModifier() but with the detail property equals detail.
let detail = SyntaxFactory.makeUnknown("").withLeadingTrivia(trivia)

// This will create a new TokenSyntax with the same information that 
// makeUnknown("") but with the LeadingTrivia property equals trivia.
SyntaxFactory.makeBlankDeclModifier().withDetail(
    SyntaxFactory.makeUnknown("").withLeadingTrivia(trivia)
)

LucianoPAlmeida

import SwiftSyntax

class FindPublicExtensionDeclVisitor: SyntaxVisitor {
    override func visit(_ node: ExtensionDeclSyntax) -> SyntaxVisitorContinueKind {
        if node.modifiers?.contains(where: { $0.name.tokenKind == .publicKeyword }) == true {
            // Do something if you find a `public extension` declaration.
        }
        return SyntaxVisitorContinueKind.skipChildren
    }
}