February 2018
Intermediate to advanced
298 pages
8h 22m
English
Content preview from Learn ECMAScript - Second Edition
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The typeof operator
The typeof operator is used to determine the type of value a particular variable/constant is held for Symbol, typeof outputs symbol. Here is an example to demonstrate the same:
const s = Symbol();console.log(typeof s); //Outputs "symbol"
Using the typeof operator is the only way to identify whether a variable holds a symbol.
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