Utilities for content negotiation described in Section 5.3 of RFC 7231.
const supported = ['text/html', 'image/webp'];
const accept = 'text/html,image/avif,image/webp,image/apng,*/*;q=0.8';
negotiate(supported, accept); // → 'text/html'
negotiate([], accept); // → null
const generator = parseAcceptStatements('v1,v2;q=0.9,v3;q=0.8');
generator.next().value; // → {value: 'v1', q: 1}
generator.next().value; // → {value: 'v2', q: 0.9}
generator.next().value; // → {value: 'v3', q: 0.8}
generator.next(); // → {value: undefined, done: true}
parseNegotiationItem('text/html;charset=utf-8;foo=1');
// → {value: 'text/html', parameters: {charset: 'utf-8', foo: '1'}}