41. There is also a yield break statement, in which control is unconditionally returned to the caller of the iterator . 42. When " flag " is an explicit nil or omitted, this returns an iterator for number keys. 43. A pull parser creates an iterator that sequentially visits the various elements, attributes, and data in an XML document. 44. Adding or removing elements by calling the methods of container ( also from the same thread ) makes the iterator unusable. 45. Thus, no matter what type of indexing method any implementation of the element uses, it will have the appropriate Iterator . 46. Each Iterator is given a reference to a specific algorithm ( such as spell check, grammar check, etc . ). 47. The ParaSail parallel programming language supports several kinds of iterators, including a general " for each " iterator over a container: 48. Here is a small excerpt from the definition of the interfaces List and Iterator in package " " ": 49. It is possible for users to create their own iterator types by deriving subclasses from the standard std : : iterator class template. 50. It is possible for users to create their own iterator types by deriving subclasses from the standard std : : iterator class template.
