function isKey(value, object) {
    if (Array.isArray(value)) {
        return false
    }
    const type = typeof value
    if (type === 'number' || type === 'boolean' || value == null) {
        return true
    }
    return reIsPlainProp.test(value) || !reIsDeepProp.test(value) ||
    (object != null && value in Object(object))
}
Used to match property names within property paths.