in shared/java/FontFeature.java [64:75]
public static FontFeature parseOne(String s) {
Matcher m = _featurePattern.matcher(s);
if (!m.matches())
throw new IllegalArgumentException("Can’t parse FontFeature: " + s);
int value = m.group("value") != null ? Integer.parseInt(m.group("value"))
: m.group("sign") == null ? 1
: "-".equals(m.group("sign")) ? 0
: 1;
long start = m.group("start") == null ? 0 : Long.parseLong(m.group("start"));
long end = m.group("end") == null ? Long.MAX_VALUE : Long.parseLong(m.group("end"));
return new FontFeature(m.group("tag"), value, start, end);
}