Symbol predicates

Specification: proposal-symbol-predicates

Modules

esnext.symbol.is-registered-symbol, esnext.symbol.is-well-known-symbol.

class Symbol {
  static isRegisteredSymbol(value: any): boolean;
  static isWellKnownSymbol(value: any): boolean;
}

CommonJS entry points

core-js/proposals/symbol-predicates-v2
core-js(-pure)/full/symbol/is-registered-symbol
core-js(-pure)/full/symbol/is-well-known-symbol

Example

Symbol.isRegisteredSymbol(Symbol.for('key')); // => true
Symbol.isRegisteredSymbol(Symbol('key')); // => false

Symbol.isWellKnownSymbol(Symbol.iterator); // => true
Symbol.isWellKnownSymbol(Symbol('key')); // => false