constructor - nberlette/is GitHub Wiki
function isConstructor<T>(it: unknown): it is Constructor<T>;Checks whether a given value is a constructor function.
In this context, a constructor is defined as a function with a prototype own
property that contains an object with an own constructor property that points
back to the constructor function itself.
| Name | Info |
|---|---|
it |
The value to check. |
true if the value is a constructor function; otherwise, false.
Guards
import { isConstructor } from "jsr:@nick/is/constructor";
class Foo {}
console.log(isConstructor(Foo)); // true
console.log(isConstructor(Foo.prototype.constructor)); // true
console.log(isConstructor(class {})); // true
console.log(isConstructor(function () {})); // true
console.log(isConstructor({})); // false
console.log(isConstructor(null)); // false
console.log(isConstructor(Foo.prototype)); // false
console.log(isConstructor(() => new Foo())); // falseRepresents a constructor function that creates instances of type T.
Types
-
T(default:unknown) -
Aextendsreadonly unknown[](default:readonly unknown[])
readonly prototype: Prototype<T, this>;