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Function: isInstanceOf() ​

ts
function isInstanceOf<T>(
  value: unknown,
  type: string,
  ctor?: (...args: any[]) => T,
): value is T;

Defined in: src/lib/utils/guards.ts:17

Returns true if value is an instance of the class identified by type (and optionally ctor).

Type Parameters ​

Type ParameterDescription
TThe expected instance type.

Parameters ​

ParameterTypeDescription
valueunknownThe value to test.
typestringThe constructor name to compare against when instanceof is unavailable.
ctor?(...args: any[]) => TOptional constructor to use for instanceof and Symbol.hasInstance checks.

Returns ​

value is T

true when value is an instance of the class described by type/ctor.

Remarks ​

Performs three checks in order: instanceof ctor, Symbol.hasInstance, then constructor-name comparison. The constructor-name fallback handles cross-realm cases where instanceof fails.