Guards the value to be an object of a generic type variable Obj. The function guards only generic objects, not specific objects.

const guardObject = <
  Obj extends object,
  Payload extends object = object
  value: Obj,
  callback?: ResultCallback<Obj, Payload>,
  payload?: Payload
): value is Obj => isObject(value, callback, payload);

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Generic type variables


A generic type variable Obj constrained by object indicates captured object type of the given value via the return type and the value parameter of the provided callback function ResultCallback type.


The Payload generic type variable constrained by object indicates the type of optional parameter payload of the supplied callback function and payload optional parameter of the guardObject() function from which it captures its value.


value: Obj

An object of a generic type variable Obj, by default of the type captured from itself to guard.

callback?: ResultCallback<Type, Payload>

The optional callback function of ResultCallback type with parameters, the value that has been checked, the result of this check, and payload of generic type variable Payload with optional properties from the provided payload, to handle them before the result return. By default, it uses resultCallback() function.

payload?: Payload

An optional object of the generic type variable Payload is assigned to the payload of the given callback function.

Return type

value is Obj

The return type is a boolean as the result of its statement indicating the value is an object of a generic type variable Obj, by default of type captured from the supplied value.


The return value is a boolean indicating whether the provided value is an object of a generic type variable Obj.

Example usage

// Example usage.
import { guardObject } from '@angular-package/type';

class Person {}
const o = {};
const p = new Person();

guardObject(o); // true, value is {}
guardObject(p); // true, value is Person

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