Should I Use Curly Braces for Single ES6 Imports?

ES6 Import Best Practices: Curly Braces for Single Imports

When importing modules in ES6, the use of curly braces surrounding the imported item has sparked some confusion. This article aims to shed light on the appropriate usage of curly braces for single imports.

Default Imports

If a module contains a default export, you can import it without curly braces. A default export is the primary export of a module and is typically the module's main functionality. For example:

// ModuleA.js
export default function sayHello() {
  console.log("Hello!");
}

To import ModuleA, you can write:

import ModuleA from "./ModuleA";

Named Imports

When importing specific named exports from a module, you must use curly braces to enclose the exported variables or functions. These exports are members of the module that can be exported individually. For example:

// ModuleB.js
export const name = "John";
export const age = 25;

To import the named exports from ModuleB, you can use:

import { name, age } from "./ModuleB";

When to Use Curly Braces for Single Imports

In general, you should never use curly braces for a single import if it is a default export. If a module has multiple named exports and you wish to import only one, then curly braces are necessary.

For instance, if ModuleC has a default export and a named export called counter, you should import them as follows:

// ModuleC.js
export default {
  counter: 0
};

export const counterIncrement = () => {
  this.counter++;
};

// Import without curly braces for default export
import moduleC from "./ModuleC";

// Import with curly braces for named export
import { counterIncrement } from "./ModuleC";

Conclusion

Understanding the distinction between default and named exports, as well as the appropriate use of curly braces for single imports, is crucial for efficient and error-free ES6 development. By following these best practices, you can ensure that your imports are concise, clear, and maintainable.

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