from

In JavaScript, from is a contextual keyword that names the source module in an import declaration or a re-exporting export statement. The module specifier after it must be a string literal, such as "./utils.mjs" or "node:fs".

In an import declaration, from follows the list of bindings to import. In an export statement, it turns the statement into a re-export that passes another module’s bindings along without creating local ones. A side-effect import such as import "./setup.mjs"; has no bindings and no from clause. The host resolves the specifier. Node.js and browsers treat relative paths as URLs relative to the current module.

Both forms are module syntax, which only works in a module. Outside these clauses, from isn’t reserved and stays a valid identifier, even in modules. The dynamic import() syntax takes the specifier as an argument and doesn’t use from. The keyword was added together with modules in ES2015.

import <bindings> from "<specifier>" [with { <attributes> }];
export <bindings> from "<specifier>" [with { <attributes> }];

export const toCelsius = (f) => ((f - 32) * 5) / 9;
export const toFahrenheit = (c) => (c * 9) / 5 + 32;

import { toCelsius } from "./units.mjs";
import { format } from "node:util";

console.log(format("%d degrees Celsius", toCelsius(212)));

$ node convert.mjs
100 degrees Celsius

> const from = "[email protected]";
undefined
> from
'[email protected]'