(You can read more about the language feature here.)
Symbols are values, so JsGetValueType now has a new type it will return, JsSymbol. You can create a new Symbol through JsRT using JsCreateSymbol. You can get a property ID from a symbol using JsGetPropertyIdFromSymbol, and you can get the symbol from a property ID (assuming it is a property ID created from a symbol) using JsGetSymbolFromPropertyId. JsGetPropertyIdType will tell you whether a property ID was created using a symbol or a property name. You can use GetOwnPropertySymbols to get any properties on an object that are indexed using symbols (as they won’t show up in GetOwnPropertyNames).
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