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javascript instance accessor property

Symbol.prototype.description

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The description accessor property of Symbol values returns a string containing the description of this symbol, or undefined if the symbol has no description.

Interactive exampleOpen the canonical MDN source to run this embedded demo.
console.log(Symbol("desc").description);
// Expected output: "desc"

console.log(Symbol.iterator.description);
// Expected output: "Symbol.iterator"

console.log(Symbol.for("foo").description);
// Expected output: "foo"

console.log(`${Symbol("foo").description}bar`);
// Expected output: "foobar"

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

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also