public StringSubject factValue(String key, int index) {
    checkArgument(index >= 0, "index must be nonnegative: %s", index);
    return doFactValue(key, index);
  }
public StringSubject factValue ( String key , int index ) { checkArgument ( index >= 0 , "index must be nonnegative: %s" , index ) ; return doFactValue ( key , index ) ; }
Returns a subject for the value of the {@code index}-th instance of the fact with the given
name. Most Truth failures do not contain multiple facts with the same key, so most tests should
use {@linkplain #factValue(String) the other overload} of {@code factValue}.