dump() example

DumpView.swift

//  DumpExample
//  This SwiftUI View explores use of the dump() function for manipulating the debugging display
//  of large, structured data.
//
//  Created by Quinn McHenry on 2/17/22.

import SwiftUI

struct ContentView: View {

    @State private var maxDepth = 0
    @State private var maxItems = 0

    private let maxMaxDepth = 6 // when maxDepth == this, use .max instead
    private let maxMaxItems = 11 // when maxItems == this, use .max instead

    private let sample = Alpha.sample()

    var body: some View {

        VStack {
            Text("dump()")
                .font(.title)
                .padding()

            Stepper("maxDepth: \(maxDepth == maxMaxDepth ? ".max" : "\(maxDepth)")",
                    value: $maxDepth, in: 0...maxMaxDepth, onEditingChanged: showDump)

            Stepper("maxItems: \(maxItems == maxMaxItems ? ".max" : "\(maxItems)")",
                    value: $maxItems, in: 0...maxMaxItems, onEditingChanged: showDump)

        }
        .padding(50)
    }

    func showDump(_ changed: Bool) {
        print("maxDepth = \(maxDepth) maxItems = \(maxItems)")
        print("print() ---")
        print(sample)
        print("dump() ---")
        dump(sample, //name: "Name here!", indent: 10,
             maxDepth: maxDepth == maxMaxDepth ? .max : maxDepth,
             maxItems: maxItems == maxMaxItems ? .max : maxItems)

        /// Simple usage `dump(sample)` defaults to `dump(sample, maxDepth: .max, maxItems: .max)`
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

/// Fake data for testing

struct Alpha {
    let s: String
    let betas: [Beta]

    static func sample() -> Self {
        Alpha(s: "the alpha", betas: [
            Beta(s: "beta one", deltas: [.sample(1), .sample(10), .sample(100)]),
            Beta(s: "beta two", deltas: [.sample(2), .sample(20), .sample(200)]),
            Beta(s: "beta three", deltas: [.sample(3), .sample(30), .sample(300)]),
            Beta(s: "beta four", deltas: [.sample(4), .sample(20), .sample(400)]),
        ])
    }
}

struct Beta {
    let s: String
    let deltas: [Delta]
}

struct Delta {
    let i: Int
    let s: String

    static func sample(_ i: Int) -> Self {
        Delta(i: i, s: "delta \(i)")
    }
}