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Lint Rule noNewSymbol

website/src/pages/lint/rules/noNewSymbol.md

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noNewSymbol (since v0.10.0)

This rule is recommended by Rome.

Disallow new operators with the Symbol object.

Symbol cannot be instantiated. This results in throwing a TypeError.

Source: https://eslint.org/docs/latest/rules/no-new-symbol

Examples

Invalid

jsx
var foo = new Symbol('foo');
<pre class="language-text"><code class="language-text">correctness/noNewSymbol.js:1:11 <a href="https://docs.rome.tools/lint/rules/noNewSymbol">lint/correctness/noNewSymbol</a> <span style="color: #000; background-color: #ddd;"> FIXABLE </span> ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ <strong><span style="color: Tomato;"> </span></strong><strong><span style="color: Tomato;">✖</span></strong> <span style="color: Tomato;"><strong>Symbol</strong></span><span style="color: Tomato;"> cannot be called as a constructor.</span> <strong><span style="color: Tomato;"> </span></strong><strong><span style="color: Tomato;">&gt;</span></strong> <strong>1 │ </strong>var foo = new Symbol('foo'); <strong> │ </strong> <strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong> <strong>2 │ </strong> <strong><span style="color: rgb(38, 148, 255);"> </span></strong><strong><span style="color: rgb(38, 148, 255);">ℹ</span></strong> <span style="color: rgb(38, 148, 255);">Suggested fix</span><span style="color: rgb(38, 148, 255);">: </span><span style="color: rgb(38, 148, 255);">Remove </span><span style="color: rgb(38, 148, 255);"><strong>new</strong></span><span style="color: rgb(38, 148, 255);">.</span> <strong> </strong><strong> 1 │ </strong>var<span style="opacity: 0.8;">·</span>foo<span style="opacity: 0.8;">·</span>=<span style="opacity: 0.8;">·</span><span style="color: Tomato;">n</span><span style="color: Tomato;">e</span><span style="color: Tomato;">w</span><span style="opacity: 0.8;"><span style="color: Tomato;">·</span></span>Symbol('foo'); <strong> </strong><strong> │ </strong> <span style="color: Tomato;">-</span><span style="color: Tomato;">-</span><span style="color: Tomato;">-</span><span style="color: Tomato;">-</span> </code></pre>

Valid

jsx
var bar = Symbol('bar');
function baz() {
    function Symbol() { }
    new Symbol();
}