code: public static <T> int findIndexOf(T[] self, int startIndex, @ClosureParams(FirstParam.Component.class) Closure condition) {
          return findIndexOf(new ArrayIterator<T>(self), startIndex, condition);
      }
docs: Iterates over the elements of an Array, starting from a
  specified startIndex, and returns the index of the first item that satisfies the
  condition specified by the closure.
  
  @param self       an Array
  @param startIndex start matching from this index
  @param condition  the matching condition
  @return an integer that is the index of the first matched object or -1 if no match was found
  @since 2.5.0