Modules

Sometimes you need to use a type which is declared in other module. So, you need a mechanism of importing/exporting types from different modules. Hegel provides ECMAScript modules like syntax for this case.

// ./modules/a.js
export class A {}
export type B = {};
export default class Main {}
export const MY_OWN_CONST = 42;

// ./modules/b.js
import type Main, { A, B, MY_OWN_CONST } from "./b.js";
// Error: Type "22" is incompatible with type "42"
const NEW_CONST: MY_OWN_CONST = 22;

As you can see, you can import type of values without actual value importing. It means that the same as other "type imports", this imports will be removed by compiler.