simevidas/es6-modules-summary.md

## es6-modules-summary.md

      
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              es6-modules-summary.md
            
          
    ECMAScript Modules


modules are automatically strict mode
declarations inside a module are scoped to that module (not visible by other scripts)
ECMAScript does not define what import does (it’s left up to the implementation)
there is no error recovery; “if anything fails to load or link, nothing runs”
exporting:


you can export any top-level function, class, var, let, or const
export function fn() { ... };


you can export lists, which can appear anywhere in a module’s top-level scope and can be combined with other export declarations
export {a, b as bravo};


you can designate one of the exports as the default export
export default function fn() { ... }; 

// or in a list:
export {a, b as bravo, fn as default};


you can re-export from other modules (similar to import-from followed by export, except that re-exported bindings won’t be added to the current module’s scope)
export {c, d} from 'other';
export * from 'other'; // re-export everything


importing:


you can import named exports (and optionally rename them)
import {a, bravo, c as charlie} from 'module';


you can import the default export of a module (incl. CommonJS or AMD modules) by ommiting the braces
// same value as require('lodash') in CommonJS
import _ from 'lodash';


you can import both the default export and named exports at the same time
import _, {each, map} from 'lodash';
// or
import {default as _, each, map} from 'lodash';


you can import a module’s namespace object, which contains all the module’s exports as properties
import * as user from 'user'; 


Read the full blog post here.