export type Primary = Pooled(Transport.Options) | Custom(fn() -> Handler.Send)

export type Observation = { name: Str, redact: fn(Str) -> Bool }

export type Observer = { outer: fn(Observation) -> Handler.Handler, inner: fn(Observation) -> Handler.Handler }

export type Builder = {
  name: Str,
  everyClient: Bool,
  clientActions: Array[fn(Client.Client) -> Client.Client],
  handlers: Array[fn() -> Handler.Handler],
  handlerEdits: Array[fn(Array[Handler.Handler]) -> Array[Handler.Handler]],
  primary: Option[Primary],
  transportEdits: Array[fn(Transport.Options) -> Transport.Options],
  lifetime: Option[Int],
  observers: Array[Observer],
  observersCleared: Bool,
  redacted: Array[Str],
  redactWhen: Option[fn(Str) -> Bool]
}

export fn named(name: Str) -> Builder

export fn defaults() -> Builder

export fn combine(first: &Builder, second: &Builder) -> Builder

export fn lifetimeOf(builder: &Builder) -> Int

export fn redaction(builder: &Builder) -> fn(Str) -> Bool

export trait Configuring {
  fn withBaseAddress(self: &Self, address: Str) -> Self
  fn withDefaultHeader(self: &Self, name: Str, value: Str) -> Self
  fn withTimeout(self: &Self, millis: Int) -> Self
  fn withMaxResponseContentBufferSize(self: &Self, bytes: Int) -> Self
  fn withDefaultVersion(self: &Self, version: Http.Version, policy: Version.Policy) -> Self
  fn configureClient(self: &Self, action: fn(Client.Client) -> Client.Client) -> Self
  fn withHandler(self: &Self, handler: Handler.Handler) -> Self
  fn withHandlerFactory(self: &Self, make: fn() -> Handler.Handler) -> Self
  fn configureHandlers(self: &Self, edit: fn(Array[Handler.Handler]) -> Array[Handler.Handler]) -> Self
  fn withTransport(self: &Self, options: Transport.Options) -> Self
  fn configureTransport(self: &Self, edit: fn(Transport.Options) -> Transport.Options) -> Self
  fn withPrimary(self: &Self, make: fn() -> Handler.Send) -> Self
  fn withHandlerLifetime(self: &Self, millis: Int) -> Self
  fn observedBy(self: &Self, observer: Observer) -> Self
  fn withoutObservers(self: &Self) -> Self
  fn redactingHeaders(self: &Self, names: &Array[Str]) -> Self
  fn redactingWhen(self: &Self, test: fn(Str) -> Bool) -> Self
}