When Should I Use Curly Braces in ES6 Imports?

Curly Braces in ES6 Imports: Understanding When to Use Them

As JavaScript developers, it's crucial to grasp the nuances of importing modules in ES6, particularly when it comes to using curly braces. Let's delve into the details to clarify when and why we should use them.

In ES6, there are two types of imports: default imports and named imports. Default imports, as the name suggests, refer to the module's main export, while named imports target specific exports within a module.

When importing a single module, you typically don't need to enclose it in curly braces. Let's illustrate this concept. Suppose we have a file named initialState.js that exports an object:

// initialState.js
var initialState = {
    todo: {
        todos: [...]
    }
};

export default initialState;

To import this module in TodoReducer.js, you can simply write:

// TodoReducer.js
import initialState from './initialState';

However, if the module you want to import has named exports and you wish to access one of its exports, you must enclose them in curly braces. Consider the following example:

// A.js
export const name1 = 'John';
export const name2 = 'Mary';

To import specific exports from this module, you can do:

// B.js
import { name1, name2 } from './A';

In this case, the curly braces are required.

When Not to Use Curly Braces:

In general, you should avoid using curly braces when importing a single module that has only a default export. This is because curly braces are meant for importing named exports. If you enclose a default import in curly braces, it may produce unforeseen errors.

Conclusion:

Understanding when to use curly braces in ES6 imports is essential for writing clean and maintainable code. Always enclose named exports in curly braces to import them correctly. By following these guidelines, you can ensure efficient module imports in your ES6 projects.

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