# ZoneSpecification class

This class provides the specification for a forked zone.

When forking a new zone (see Zone.fork) one can override the default behavior of the zone by providing callbacks. These callbacks must be given in an instance of this class.

Handlers have the same signature as the same-named methods on Zone but receive three additional arguments:

1. the zone the handlers are attached to (the "self" zone).
2. a ZoneDelegate to the parent zone.
3. the zone that first received the request (before the request was bubbled up).

Handlers can either stop propagation the request (by simply not calling the parent handler), or forward to the parent zone, potentially modifying the arguments on the way.

## Constructors

ZoneSpecification({HandleUncaughtErrorHandler handleUncaughtError, RunHandler<R> run, RunUnaryHandler<R, T> runUnary, RunBinaryHandler<R, T1, T2> runBinary, RegisterCallbackHandler<R> registerCallback, RegisterUnaryCallbackHandler<R, T> registerUnaryCallback, RegisterBinaryCallbackHandler<R, T1, T2> registerBinaryCallback, ErrorCallbackHandler errorCallback, ScheduleMicrotaskHandler scheduleMicrotask, CreateTimerHandler createTimer, CreatePeriodicTimerHandler createPeriodicTimer, PrintHandler print, ForkHandler fork })
  Creates a specification with the provided handlers.
  const
  factory
ZoneSpecification.from(ZoneSpecification other, { HandleUncaughtErrorHandler handleUncaughtError, RunHandler<R> run, RunUnaryHandler<R, T> runUnary, RunBinaryHandler<R, T1, T2> runBinary, RegisterCallbackHandler<R> registerCallback, RegisterUnaryCallbackHandler<R, T> registerUnaryCallback, RegisterBinaryCallbackHandler<R, T1, T2> registerBinaryCallback, ErrorCallbackHandler errorCallback, ScheduleMicrotaskHandler scheduleMicrotask, CreateTimerHandler createTimer, CreatePeriodicTimerHandler createPeriodicTimer, PrintHandler print, ForkHandler fork })
  Creates a specification from `other` with the provided handlers overriding the ones in `other`.
  factory

## Properties

createPeriodicTimer → CreatePeriodicTimerHandler
  read-only
createTimer → CreateTimerHandler
  read-only
errorCallback → ErrorCallbackHandler
  read-only
fork → ForkHandler
  read-only
handleUncaughtError → HandleUncaughtErrorHandler
  read-only
print → PrintHandler
  read-only
registerBinaryCallback → RegisterBinaryCallbackHandler<R, T1, T2>
  read-only
registerCallback → RegisterCallbackHandler<R>
  read-only
registerUnaryCallback → RegisterUnaryCallbackHandler<R, T>
  read-only
run → RunHandler<R>
  read-only
runBinary → RunBinaryHandler<R, T1, T2>
  read-only
runUnary → RunUnaryHandler<R, T>
  read-only
scheduleMicrotask → ScheduleMicrotaskHandler
  read-only
hashCode → int
  The hash code for this object. [...]
  read-only, inherited
runtimeType → Type
  A representation of the runtime type of the object.
  read-only, inherited

## Methods

noSuchMethod(Invocation invocation) → dynamic
  Invoked when a non-existent method or property is accessed. [...]
  inherited
toString() → String
  Returns a string representation of this object.
  inherited

## Operators

operator ==(dynamic other) → bool
  The equality operator. [...]
  inherited