@threlte/core/dist/utilities/isInstanceOf.d.ts

A 3D framework for the web, built on top of Svelte and Three.js

import type * as THREE from 'three';
/**
 * Omit the keys that have a value of `never`.
 *
 * @example
 * ```ts
 * type Foo = {
 *   x: number
 *   y: never
 * }
 * type Bar = OmitNever<Foo> // { x: number }
 * ```
 */
type OmitNever<T> = {
    [K in keyof T as T[K] extends never ? never : K]: T[K];
};
/**
 * A type that contains all the classes in THREE that have a static `isFoo` property.
 */
type ThreeClassTypes = OmitNever<{
    [K in keyof typeof THREE]: (typeof THREE)[K] extends {
        new (...args: any[]): any;
    } ? InstanceType<(typeof THREE)[K]> extends {
        [P in `is${K}`]: boolean;
    } ? (typeof THREE)[K] : never : never;
}>;
/**
 * Check if an object is an instance of a given THREE class. Can be used as a
 * type guard and as an alternative to `instanceof` which is prone to error and
 * slower. It uses the `isFoo` property that THREE classes have to determine if
 * an object is of a particular class.
 *
 * @example
 * ```ts
 * const obj = new THREE.Object3D()
 * isInstanceOf(obj, 'Object3D') // true
 * ```
 *
 * @param obj - The object to check.
 * @param type - The class name to check against.
 * @returns `true` if the object is an instance of the class, `false` otherwise.
 */
export declare const isInstanceOf: <T extends keyof ThreeClassTypes>(obj: any, type: T) => obj is InstanceType<ThreeClassTypes[T]>;
export {};