prefer-template

Require template literals instead of string concatenation

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Some problems reported by this rule are automatically fixable by the --fix command line option

In ES2015 (ES6), we can use template literals instead of string concatenation.

var str = "Hello, " + name + "!";
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/*eslint-env es6*/

var str = `Hello, ${name}!`;
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Rule Details

This rule is aimed to flag usage of + operators with strings.

Examples

Examples of incorrect code for this rule:

Open in Playground

/*eslint prefer-template: "error"*/

var str = "Hello, " + name + "!";
var str = "Time: " + (12 * 60 * 60 * 1000);
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Examples of correct code for this rule:

Open in Playground

/*eslint prefer-template: "error"*/
/*eslint-env es6*/

var str = "Hello World!";
var str = `Hello, ${name}!`;
var str = `Time: ${12 * 60 * 60 * 1000}`;

// This is reported by `no-useless-concat`.
var str = "Hello, " + "World!";
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When Not To Use It

This rule should not be used in ES3/5 environments.

In ES2015 (ES6) or later, if you don’t want to be notified about string concatenation, you can safely disable this rule.

Version

This rule was introduced in ESLint v1.2.0.

Resources

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