no-new

Disallow new operators outside of assignments or comparisons

The goal of using new with a constructor is typically to create an object of a particular type and store that object in a variable, such as:

var person = new Person();
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It’s less common to use new and not store the result, such as:

new Person();
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In this case, the created object is thrown away because its reference isn’t stored anywhere, and in many cases, this means that the constructor should be replaced with a function that doesn’t require new to be used.

Rule Details

This rule is aimed at maintaining consistency and convention by disallowing constructor calls using the new keyword that do not assign the resulting object to a variable.

Examples of incorrect code for this rule:

/*eslint no-new: "error"*/

new Thing();
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Examples of correct code for this rule:

/*eslint no-new: "error"*/

var thing = new Thing();

Foo();
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Version

This rule was introduced in ESLint v0.0.7.

Resources

• Rule source
• Tests source