instanceOf

Callable

• instanceOf<T>(object: unknown, declaration: Constructor<T>, loose?: boolean): object is T

---

• Performs a loose instance check by comparing class names up the prototype chain if instanceof initially fails. To disable this loose check, pass false as the 3rd argument.

  import { instanceOf } from '@boost/common';
  
  if (instanceOf(error, Error)) {
      console.log(error.stack);
  }

  Generics can be used to type the object being checked. This will default to the declaration passed to the 2nd argument.

  instanceOf<ParseError>(error, Error);

  Loose checks can be useful if multiple copies of the same class declaration exists in the module tree. For example, multiple versions of the same package are imported.

  ---

  Type parameters

  • T = unknown