set.prototype.issupersetof (npm): An ESnext spec-compliant `Set.prototype.isSupersetOf` shim/polyfill/replacement that works as far down as ES3
Keywords: javascript|ecmascript|polyfill|shim|Set|Set.prototype.isSupersetOf|isSupersetOf|superset|es-shim API|es-shims|issupersetof|set