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DeferSignal

@rotorsoft/act-root

@rotorsoft/act-root / act/src / DeferSignal

Class: DeferSignal

Defined in: libs/act/src/types/errors.ts:342

The control-flow signal a reaction handler throws to defer itself. Unlike an error, a defer is not a failure: the dispatcher (build_handle) catches it and produces a HandleResult.defer — the triggering events stay pending (watermark not advanced), retry is not bumped, and the drain re-visits the stream at the resolved due-time.

DeferSignal is the imperative escape hatch and is re-exported from the package root, so reaction code can throw it directly when a static .defer(when) step isn't expressive enough (a deadline computed from loaded state, say). It carries the unresolved DeferWhen; the dispatcher resolves it against the triggering event it is already dispatching (via resolve_defer_at), which is what anchors { after } and the at function form to that event and keeps the due-time derivable. Fully dynamic times go through { at: someDate }.

Modeled as an Error subclass — like NonRetryableError — so it rides the existing try/catch in the handler loop instead of needing a separate return channel through every dispatcher signature. The compiled autoclose reaction throws the same signal.

Extends​

  • Error

Constructors​

Constructor​

new DeferSignal(when): DeferSignal

Defined in: libs/act/src/types/errors.ts:349

Parameters​

when​

DeferWhen

Returns​

DeferSignal

Overrides​

Error.constructor

Properties​

cause?​

optional cause?: unknown

Defined in: node_modules/.pnpm/typescript@6.0.3/node_modules/typescript/lib/lib.es2022.error.d.ts:24

Inherited from​

Error.cause

message​

message: string

Defined in: node_modules/.pnpm/typescript@6.0.3/node_modules/typescript/lib/lib.es5.d.ts:1075

Inherited from​

Error.message

name​

name: string

Defined in: node_modules/.pnpm/typescript@6.0.3/node_modules/typescript/lib/lib.es5.d.ts:1074

Inherited from​

Error.name

stack?​

optional stack?: string

Defined in: node_modules/.pnpm/typescript@6.0.3/node_modules/typescript/lib/lib.es5.d.ts:1076

Inherited from​

Error.stack

when​

readonly when: DeferWhen

Defined in: libs/act/src/types/errors.ts:347

The unresolved schedule. The dispatcher turns this into an absolute due-time by resolving it against the triggering event.

stackTraceLimit​

static stackTraceLimit: number

Defined in: node_modules/.pnpm/@types+node@22.20.5/node_modules/@types/node/globals.d.ts:68

The Error.stackTraceLimit property specifies the number of stack frames collected by a stack trace (whether generated by new Error().stack or Error.captureStackTrace(obj)).

The default value is 10 but may be set to any valid JavaScript number. Changes will affect any stack trace captured after the value has been changed.

If set to a non-number value, or set to a negative number, stack traces will not capture any frames.

Inherited from​

Error.stackTraceLimit

Methods​

captureStackTrace()​

static captureStackTrace(targetObject, constructorOpt?): void

Defined in: node_modules/.pnpm/@types+node@22.20.5/node_modules/@types/node/globals.d.ts:52

Creates a .stack property on targetObject, which when accessed returns a string representing the location in the code at which Error.captureStackTrace() was called.

const myObject = {};
Error.captureStackTrace(myObject);
myObject.stack;  // Similar to `new Error().stack`

The first line of the trace will be prefixed with ${myObject.name}: ${myObject.message}.

The optional constructorOpt argument accepts a function. If given, all frames above constructorOpt, including constructorOpt, will be omitted from the generated stack trace.

The constructorOpt argument is useful for hiding implementation details of error generation from the user. For instance:

function a() {
  b();
}

function b() {
  c();
}

function c() {
  // Create an error without stack trace to avoid calculating the stack trace twice.
  const { stackTraceLimit } = Error;
  Error.stackTraceLimit = 0;
  const error = new Error();
  Error.stackTraceLimit = stackTraceLimit;

  // Capture the stack trace above function b
  Error.captureStackTrace(error, b); // Neither function c, nor b is included in the stack trace
  throw error;
}

a();

Parameters​

targetObject​

object

constructorOpt?​

Function

Returns​

void

Inherited from​

Error.captureStackTrace

prepareStackTrace()​

static prepareStackTrace(err, stackTraces): any

Defined in: node_modules/.pnpm/@types+node@22.20.5/node_modules/@types/node/globals.d.ts:56

Parameters​

err​

Error

stackTraces​

CallSite[]

Returns​

any

See​

https://v8.dev/docs/stack-trace-api#customizing-stack-traces

Inherited from​

Error.prepareStackTrace