https://github.com/chenhaiteng/swiftclamping
https://github.com/chenhaiteng/swiftclamping
Last synced: 4 months ago
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- Host: GitHub
- URL: https://github.com/chenhaiteng/swiftclamping
- Owner: chenhaiteng
- License: mit
- Created: 2024-03-04T06:00:07.000Z (over 1 year ago)
- Default Branch: main
- Last Pushed: 2024-04-02T06:04:47.000Z (about 1 year ago)
- Last Synced: 2025-02-12T21:04:27.730Z (4 months ago)
- Language: Swift
- Size: 19.5 KB
- Stars: 0
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# Swift-Clamping
## Purpose:
1. For values that have upper and lower bound, provide a way to not write duplicate code.
2. In swift, when one try to preprocess an property before apply it, it needs following code:
```swift
private var _computedVarStorage: Int
public var computedVar: Int {
get {
return _computedVarStorage
}
set {
_computedVarStorage = newValue*10
}
}
```
Because the get/set syntax will change variable to computed variable, it always need write a getter, even through we want a write-only property.
Also, to keep the modified value, a extra storage variable is needed, and it looks ugly.
3. In additionally, we also want the solution could be apply to protocol.
## Solution:
1. Use @propertyWrapper to apply clamp; replace max, min and degree into one declaration.
```swift
@Clamping(max: 0.0, min: 360.0) var degree = 0.0
@Clamping(0.0...1.0) var value = 0.5
```
2. In some situation, it need modify the range later, property wrapper use projectedValue to implement this requirement:
```swift
@Clamping(0.0...1.0) var value = 0.5
$value = 0.0...10.0
```
3. Although @propertyWrapper is useful, it hard to apply this mechanism to protocol. However, there has a workaround:
```swift
protocol ClampProtocol {
var degree: Double // Can declare as @Clamping
var range: ClosedRange // Can map to projectedValue in @Clamping
}
struct ClampStruct {
@Clamping(0.0...360.0) var degree = 0.0
var range: ClosedRange {
get { $degree }
set { $degree = newValue }
}
}
```
With this workaround, all class/struct implement ClampProtocol can apply @Clamping to simplify the effort to write clamp function, and keep it interface clear.
The detail about the implementation of @Clamping could be refer to : [Clamping.swift](Sources/SwiftClamping/Clamping.swift)
## Installation:
### CocoaPods
SwiftClamping is available through [CocoaPods](https://cocoapods.org). To install
it, simply add the following line to your Podfile:
```ruby
pod 'SwiftClamping'
```
### Swift Package Manager
#### - Add to Xcode
1. File > Swift Packages > Add Package Dependency...
2. Choose Project you want to add SwiftClamping
3. Paste repository https://github.com/chenhaiteng/SwiftClamping.git
4. Rules > Version: Up to Next Major 1.0.1
It's can also apply Rules > Branch : Main to access latest code.
**Note:** It might need to link SwiftClamping to your target maunally.
1. Open *Project Editor* by tap on root of project navigator
2. Choose the target you want to use SwiftClamping.
3. Choose **Build Phases**, and expand **Link Binary With Libraries**
4. Tap on **+** button, and choose SwiftClamping to add it.
#### - Add to SPM package
```swift
dependencies: [
.package(url: "https://github.com/chenhaiteng/SwiftClamping.git", from: "1.0.1")
],
targets: [
.target(
name: "MyPackage",
dependencies: ["SwiftClamping"]),
]
```
## References:
[Property Wrapper - Swift Doc](https://docs.swift.org/swift-book/LanguageGuide/Properties.html#ID617)
[Property Wrapper(SE-0258) - Swift Evolution](https://github.com/apple/swift-evolution/blob/master/proposals/0258-property-wrappers.md)
[Swift: Why does a variable with a setter must also have a getter? - stackoverflow](https://stackoverflow.com/a/34677538/505763)
[PropertyWrappers and protocol declaration? - stackoverflow](https://stackoverflow.com/a/57657870/505763)
---
