@ayonli/jsext/cjs/class.js

A JavaScript extension package for building strong and modern applications.

'use strict';

var mixin$1 = require('./mixin.js');

/**
 * This module includes functions for dealing with classes.
 * @module
 */
/** @deprecated import `mixin` from `@ayonli/jsext/mixin` instead. */
const mixin = mixin$1.default;
/**
 * Checks if a value is a class/constructor.
 *
 * @example
 * ```ts
 * import { isClass } from "@ayonli/jsext/class";
 *
 * console.assert(isClass(class Foo { }));
 * console.assert(!isClass(function foo() { }));
 * ```
 */
function isClass(value) {
    if (typeof value !== "function")
        return false;
    if ([String, Number, Boolean, BigInt, Symbol].includes(value)) {
        return false;
    }
    // async function or arrow function
    if (value.prototype === undefined)
        return false;
    // generator function or malformed inheritance
    if (value.prototype.constructor !== value)
        return false;
    const str = value.toString();
    // ES6 class
    if (str.slice(0, 5) === "class")
        return true;
    const name0 = value.name[0];
    if (name0 && name0 >= "A" && name0 <= "Z" && str.includes("[native code]"))
        return true;
    return false;
}
/**
 * Checks if a class is a subclass of another class.
 *
 * @example
 * ```ts
 * import { isSubclassOf } from "@ayonli/jsext/class";
 *
 * class Moment extends Date {}
 *
 * console.assert(isSubclassOf(Moment, Date));
 * console.assert(isSubclassOf(Moment, Object)); // all classes are subclasses of Object
 * ```
 */
function isSubclassOf(ctor1, ctor2) {
    return typeof ctor1 === "function"
        && typeof ctor2 === "function"
        && ctor1.prototype instanceof ctor2;
}

exports.isClass = isClass;
exports.isSubclassOf = isSubclassOf;
exports.mixin = mixin;
//# sourceMappingURL=class.js.map