Initial Commit

.swiftpm/xcode/xcuserdata/julian.xcuserdatad/xcschemes/xcschememanagement.plist

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+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>SchemeUserState</key>
+	<dict>
+		<key>Loadability.xcscheme_^#shared#^_</key>
+		<dict>
+			<key>orderHint</key>
+			<integer>0</integer>
+		</dict>
+	</dict>
+	<key>SuppressBuildableAutocreation</key>
+	<dict>
+		<key>Loadability</key>
+		<dict>
+			<key>primary</key>
+			<true/>
+		</dict>
+	</dict>
+</dict>
+</plist>

CODE_OF_CONDUCT.md

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+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to making participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, sex characteristics, gender identity and expression,
+level of experience, education, socio-economic status, nationality, personal
+appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+ advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+ address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+ professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community. Examples of
+representing a project or community include using an official project e-mail
+address, posting via an official social media account, or acting as an appointed
+representative at an online or offline event. Representation of a project may be
+further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at [email protected]. All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
+
+[homepage]: https://www.contributor-covenant.org
+
+For answers to common questions about this code of conduct, see
+https://www.contributor-covenant.org/faq

CONTRIBUTING.md

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+# Loadability Contribution Guide
+
+*Adapted from the [Plot Contribution Guide](https://github.com/JohnSundell/Plot/blob/master/CONTRIBUTING.md)*
+
+Welcome to the **Loadability Contribution Guide**, which aims to give you all the information you need to contribute to Loadability. Thank you for your interest in contributing to this project!
+
+## Bugs, feature requests and support
+
+### I found a bug, how do I report it?
+
+If you find a bug, such as loading or caching not working correctly, please file a detailed Github Issue containing all of the information necessary to reproduce the bug. This helps us to quickly understand the bug and triage it.
+
+### I have an idea for a feature request
+
+Awesome! You can either create a Github Issue describing your idea and how it would improve the project, or create a Pull Request with your feature. Creating a Pull Request contributes to the project and makes it more likely your idea will be added!
+
+### I have a question
+
+Please make sure you read the documentation (inline in the source files) and [README](README.md) carefully. If your question is still not answered, file a Github Issue detailing your question and what steps you took already.
+
+## Project structure
+
+Loadability is structured in the default way for Swift Packages. Source code is in the `Source/Loadability` directory, with each type in a separate file.
+
+## Conclusion
+
+Hopefully this document helped you better understand how Loadability is structured and the best way to get help or contribute to the project. Thanks again for the interest!

LICENSE

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+MIT License
+
+Copyright (c) 2021 Julian Schiavo
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

Package.swift

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+// swift-tools-version:5.3
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "Loadability",
+    platforms: [.iOS(.v14), .macOS(.v11), .watchOS(.v7)],
+    products: [
+        .library(name: "Loadability", targets: ["Loadability"]),
+    ],
+    dependencies: [
+        // Dependencies declare other packages that this package depends on.
+        // .package(url: /* package url */, from: "1.0.0"),
+    ],
+    targets: [
+        .target(name: "Loadability", dependencies: []),
+    ]
+)

README.md

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+# Loadability
+
+A description of this package.

Sources/Loadability/Caching/AnySharedCache.swift

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+/// A shared cache.
+public protocol AnySharedCache {
+    associatedtype Key: Hashable & Identifiable
+    associatedtype Value
+
+    static subscript(key: Key) -> Value? { get set }
+    static func isValueStale(_ key: Key) -> Bool
+}

Sources/Loadability/Caching/Cache.swift

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+import Foundation
+
+/// A mutable collection used to store key-value pairs that are subject to eviction when resources are low.
+public class Cache<Key: Hashable & Identifiable, Value> {
+
+    /// Whether the cache automatically removes stale items.
+    final let autoRemoveStaleItems: Bool
+
+    /// The wrapped `NSCache`.
+    final let _cache = NSCache<_Key, _Entry>()
+
+    // MARK: - Public
+
+    /// Creates a new `Cache`
+    /// - Parameter autoRemoveStaleItems: Whether to automatically remove stale items, `false` by default.
+    public init(shouldAutomaticallyRemoveStaleItems autoRemoveStaleItems: Bool = false) {
+        self.autoRemoveStaleItems = autoRemoveStaleItems
+    }
+
+    /// Accesses the value associated with the given key for reading and writing. When you assign a value for a key and that key already exists, the cache overwrites the existing value. If the cache doesn’t contain the key, the key and value are added as a new key-value pair. If you assign `nil` as the value for the given key, the cache removes that key and its associated value.
+    public final subscript(key: Key) -> Value? {
+        get {
+            value(for: key)
+        }
+        set {
+            guard let value = newValue else {
+                removeValue(forKey: key)
+                return
+            }
+
+            updateValue(value, forKey: key)
+        }
+    }
+
+    /// Whether the value associated with the `key` is stale. Returns `true` if the key is not in the cache.
+    /// - Parameter key: The key to find in the cache.
+    /// - Returns: Whether the value associated with the `key` is stale.
+    final func isValueStale(forKey key: Key) -> Bool {
+        guard let value = entry(for: key) else {
+            return true
+        }
+
+        return Date() > value.expirationDate
+    }
+
+    // MARK: - Internal
+
+    /// Accesses the value associated with the given key.
+    /// - Parameter key: The key to find in the cache.
+    /// - Returns: The value associated with `key` if `key` is in the cache; otherwise, `nil`.
+    final func value(for key: Key) -> Value? {
+        entry(for: key)?.value
+    }
+
+    /// Accesses the entry associated with the given key.
+    /// - Parameter key: The key to find in the cache.
+    /// - Returns: The entry associated with `key` if `key` is in the cache; otherwise, `nil`.
+    final func entry(for key: Key) -> _Entry? {
+        let key = _Key(key)
+        return entry(for: key)
+    }
+
+    /// Accesses the entry associated with the given key.
+    /// - Parameter key: The key to find in the cache.
+    /// - Returns: The entry associated with `key` if `key` is in the cache; otherwise, `nil`.
+    private final func entry(for key: _Key) -> _Entry? {
+        _cache.object(forKey: key)
+    }
+
+    /// Updates the cached value for the given key, or adds the key-value pair to the cache if the key does not exist.
+    /// - Parameters:
+    ///   - value: The new value to add to the cache.
+    ///   - key: The key to associate with `value`. If `key` already exists in the cache, `value` replaces the existing associated value. If `key` isn’t already a key of the cache, the (`key`, `value`) pair is added.
+    ///   - expirationDate: The date at which the entry will become stale, and be reloaded.
+    final func updateValue(_ value: Value, forKey key: Key, expirationDate: Date = Date().addingTimeInterval(3600)) {
+        let _key = _Key(key)
+        let entry = _Entry(key: key, value: value, expirationDate: expirationDate)
+        updateEntry(entry, forKey: _key)
+    }
+
+    /// Updates the cached entry for the given key, or adds the entry to the cache if the key does not exist.
+    /// - Parameters:
+    ///   - entry: The entry to add to the cache.
+    ///   - key: The key to associate with `entry`. If `key` already exists in the cache, `entry` replaces the existing entry. If `key` isn’t already a key of the cache, the entry is added.
+    func updateEntry(_ entry: _Entry, forKey key: _Key) {
+        _cache.setObject(entry, forKey: key)
+    }
+
+    /// Removes the given key and its associated value from the cache.
+    /// - Parameter key: The key to remove along with its associated value.
+    private final func removeValue(forKey key: Key) {
+        let key = _Key(key)
+        removeValue(forKey: key)
+    }
+
+    /// Removes the given key and its associated value from the cache.
+    /// - Parameter key: The key to remove along with its associated value.
+    private final func removeValue(forKey key: _Key) {
+        _cache.removeObject(forKey: key)
+    }
+
+    /// Empties the cache.
+    private final func removeAll() {
+        _cache.removeAllObjects()
+    }
+
+    // MARK: - Wrapped Classes
+
+    /// A wrapper for a `Key`
+    final class _Key: NSObject {
+        /// The wrapped `Key`
+        let key: Key.ID
+
+        /// Creates a new wrapper for a key.
+        /// - Parameter key: The key to wrap
+        init(_ key: Key) {
+            self.key = key.id
+        }
+
+        override var hash: Int {
+            key.hashValue
+        }
+
+        override func isEqual(_ object: Any?) -> Bool {
+            guard let value = object as? Self else { return false }
+            return value.key == key
+        }
+    }
+
+    /// A wrapper for a key-value pair.
+    final class _Entry {
+        /// The key
+        let key: Key
+
+        /// The value
+        let value: Value
+
+        /// The expiration date of the object
+        let expirationDate: Date
+
+        /// Creates a new wrapper for a key-value pair.
+        /// - Parameters:
+        ///   - key: The key
+        ///   - value: The value
+        ///   - expirationDate: The expiration date, at which point the data will be reloaded
+        init(key: Key, value: Value, expirationDate: Date) {
+            self.key = key
+            self.value = value
+            self.expirationDate = expirationDate
+        }
+    }
+}
+
+extension Cache._Entry: Codable where Key: Codable, Value: Codable {}