which-collection
Which kind of Collection (Map, Set, WeakMap, WeakSet) is this JavaScript value? Works cross-realm, without `instanceof`, and despite Symbol.toStringTag.
is-weakmap
Is this value a JS WeakMap? This module works cross-realm/iframe, and despite ES6 @@toStringTag.
is-weakset
Is this value a JS WeakSet? This module works cross-realm/iframe, and despite ES6 @@toStringTag.