Importing & exporting
Last updated: 2025-01-23
To build composable programs, it is necessary to be able to import and export functions from other modules. This is accomplished by using ECMA script modules in Deno.
To export a function, you use the export keyword.
./util.ts
export function sayHello(thing: string) {
console.log(`Hello, ${thing}!`);
}You can also export types, variables, and classes.
./util.ts
export interface Foo {}
export class Bar {}
export const baz = "baz";To import things from files other files can use the import keyword.
./main.ts
import { sayHello } from "./util.ts";
sayHello("World");You can also import all exports from a file.
./main.ts
import * as util from "./util.ts";
util.sayHello("World");Imports don't have to be relative, they can also reference absolute file, https, or [JSR](https://jsr.io) URLs.
./main.ts
import { camelCase } from "jsr:@luca/cases@1";
console.log(camelCase("hello world")); // helloWorld
import OpenAI from "https://deno.land/x/openai@v4.53.0/mod.ts";
const client = new OpenAI();