Symbol.prototype.description - JavaScript 编辑

The read-only description property is a string returning the optional description of Symbol objects.

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Description

Symbol objects can be created with an optional description which can be used for debugging but not to access the symbol itself. The Symbol.prototype.description property can be used to read that description. It is different to Symbol.prototype.toString() as it does not contain the enclosing "Symbol()" string. See the examples.

Examples

Using description

Symbol('desc').toString();   // "Symbol(desc)"
Symbol('desc').description;  // "desc"
Symbol('').description;      // ""
Symbol().description;        // undefined

// well-known symbols
Symbol.iterator.toString();  // "Symbol(Symbol.iterator)"
Symbol.iterator.description; // "Symbol.iterator"

// global symbols
Symbol.for('foo').toString();  // "Symbol(foo)"
Symbol.for('foo').description; // "foo"

Specifications

Browser compatibility

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See also

• Symbol.prototype.toString()
• Polyfill: https://npmjs.com/symbol.prototype.description