runtypes/esm/utils-internal/typeOf.js

Runtime validation for static types

const typeOf = (value) => {
    const type = typeof value;
    if (type === "object") {
        if (value === null)
            return "null";
        if (Array.isArray(value))
            return "array";
        const prototype = globalThis.Object.getPrototypeOf(value);
        if (prototype === null)
            return "object";
        if (prototype.constructor.name === "Object")
            return "object";
        return prototype.constructor.name;
    }
    return type;
};
export default typeOf;