Function update

website/script/index.js:40–50

(highlights, tr)

      return Decoration.none;
    },
    update(highlights, tr) {
      highlights = RangeSet.empty;
      for (let e of tr.effects) {
        if (e.is(addHighlight)) {
          highlights = highlights.update({
            add: [highlighter.range(e.value.from, e.value.to)],
          });
        }
      }
      return highlights;
    },
    provide: (f) => EditorView.decorations.from(f),
  });
  const effects = [addHighlight.of(range)];