import { registerUnbound } from 'discourse/lib/helpers'; registerUnbound('value-at-tl', function(data, params) { var tl = parseInt(params.level, 10); if (data) { var item = data.find( function(d) { return parseInt(d.x, 10) === tl; } ); if (item) { return item.y; } else { return 0; } } });