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Older browsers (mainly Edge and IE11) as well as Node.js do not provide certain APIs (TextEncoder, fetch etc) that depends on.

The good news is that these APIs can be provided by the application using the polyfill technique.

While there are many good polyfill modules for these classes available on npm, to make the search for a version that is guaranteed to work with a little easier, the module is provided.

To install these polyfills, just import the polyfills module before start using

import '';
import {parse} from '';

Combining with other Polyfills only installs polyfills if the corresponding global symbol is undefined. This means that if another polyfill is already installed when is imported, the other polyfill will remain in effect. Since most polyfill libraries work this way, applications can mix and match polyfills by ordering the polyfill import statements appropriately (but see the remarks below for a possible caveat).

Provided Polyfills

See API Reference.


Applications should typically only install this module if they need to run under older environments. While the polyfills are only installed at runtime if the platform does not already support them, they will still be included in your application bundle, i.e. importing the polyfill module will increase your application's bundle size.

When importing polyfills for the same symbol from different libraries, the import can depend on how the other polyfill is written. to control the order of installation, you may want to use require rather than import when importing As a general rule, import statements execute before require statments.