code: @NotNull
      public Optional<IntPair<T>> findIndexed(@NotNull IndexedPredicate<? super T> predicate) {
          return findIndexed(0, 1, predicate);
      }
docs: Finds the first element and its index that matches the given predicate.
  
  <p>This is a short-circuiting terminal operation.
  
  <p>Example:
  <pre>
  predicate: (index, value) -&gt; index + value == 7
  stream: [1, 2, 3, 4, 5, 2, 0]
  index:  [0, 1, 2, 3, 4, 5, 6]
  result: Optional.of(IntPair(3, 4))
  </pre>
  
  @param predicate  the predicate to find value
  @return an {@code Optional} with {@code IntPair}
  or {@code Optional.empty()} if stream is empty or no value was found.
  @since 1.1.8