SwiftUI: Conditionally Configuring Views

View+Conditional.swift

import SwiftUI

public extension View {
    // MARK: Conditionally Configuring Views
    
    @ViewBuilder func `if`<TrueView>(
        _ condition: Bool,
        transform: (Self) -> TrueView
    ) -> some View where TrueView: View {
        if condition {
            transform(self)
        } else {
            self
        }
    }
    
    @ViewBuilder func `if`<TrueView, FalseView>(
        _ condition: Bool,
        true trueTransform: (Self) -> TrueView,
        else falseTransform: (Self) -> FalseView
    ) -> some View where TrueView: View, FalseView: View {
        if condition {
            trueTransform(self)
        } else {
            falseTransform(self)
        }
    }
    
    @ViewBuilder func ifLet<Value, TrueView>(
        _ value: Value?,
        transform: (Self, Value) -> TrueView
    ) -> some View where TrueView: View {
        if let value = value {
            transform(self, value)
        } else {
            self
        }
    }
    
    @ViewBuilder func ifLet<Value, TrueView, FalseView>(
        _ value: Value?,
        true trueTransform: (Self, Value) -> TrueView,
        else falseTransform: (Self) -> FalseView
    ) -> some View where TrueView: View, FalseView: View {
        if let value = value {
            trueTransform(self, value)
        } else {
            falseTransform(self)
        }
    }
}