AutoID

AutoID.swift

struct AutoID: Hashable {
  private var parent: AnyHashable?
  private var file: String
  private var line: UInt
  private var column: UInt
  
  init(parent: AnyHashable? = nil, file: String = #file, line: UInt = #line, column: UInt = #column) {
    self.parent = parent
    self.file = file
    self.line = line
    self.column = column
  }
}

Can be used like this

environment: { env in
    AvatarEnvironment(cancellationId: AutoID(parent: env.cancellationId))
}
...
environment: { env in
    AvatarEnvironment(cancellationId: AutoID(parent: env.cancellationId))
}

Will be pretty much the same as writing

environment: { env in
    struct CancelId: Hashable {}
    return AvatarEnvironment(cancellationId: [env.cancellationId, CancelId()])
}
...
environment: { env in
    struct CancelId: Hashable {}
    return AvatarEnvironment(cancellationId: [env.cancellationId, CancelId()])
}