Question:

For the below code:

const MY_KEY: symbol = Symbol(); let obj: object = {}; obj[MY_KEY] = 123; console.log(obj[MY_KEY]); // 123

For the below configuration tscconfig.json:

{ "compilerOptions": { "lib": ["es2015"] }, } <hr />

Files

$ ls tsconfig.json tstut.html tstut.js tstut.ts <hr />

How to resolve below error?

$ tsc --version Version 2.8.3 $ tsc tstut.ts tstut.ts(1,24): error TS2304: Cannot find name 'Symbol'. <hr />

In your configuration file (tsconfig.json), specify ECMAScript target version to 'ES2015' or later ('ES2016', 'ES2017','ES2018' or 'ESNEXT'). 'ES6' works for me, too.

{ "compilerOptions": { "target": "ES2015", } }