Function increment

src/formatter.ts:24–27

(o: Options, n = 2)

const max = (a: number, b: number) => Math.max(a, b);
const increment = (o: Options, n = 2) => ({
  ...o,
  indent: (o.indent || 0) + n,
});

function* formatChildren(a: Node, options: Options) {
  for (const child of a.children) {