Type definitions for the Trusted Types web specification as well as the associated polyfill.

Install the @types/trusted-types package and follow the official instructions. This will make the type definitions available globally within your package, and you will be able to use them directly:

if (window.trustedTypes && trustedTypes.createPolicy) {
  const policy = trustedTypes.createPolicy('my-policy', {
    createHTML: val => val.replace(/\</g, '&lt;')
  });

  const safe: TrustedHTML = policy.createHTML('<h1>Hello</h1>');
}

The @types/trusted-types entrypoint adds the Trusted Types type definitions to the global scope. This may be unattractive to library authors that want to use the type definitions, as this would pollute the global scope for all their downstream users. A second entrypoint was introduced for this use case, @types/trusted-types/lib, which exports the types without attaching them to the global scope. Libraries using that entrypoint will need to explicitly import the types that they need to use, as well as cast the window object to gain access to the trustedTypes property:

import {TrustedHTML, TrustedTypePolicy, TrustedTypesWindow} from '@types/trusted-types/lib';

const ttWindow = window as unknown as TrustedTypesWindow;
if (ttWindow.trustedTypes) {
  // ...
}

As a native web API, the Trusted Types type definitions will eventually make their way into lib.dom.d.ts. To aid with the migration, and to prevent two incompatible versions of the types from coexisting, this package will be updated to re-export the Trusted Types type definitions from lib.dom.d.ts as soon as they become available.