Difference between Iterator and Iterable [duplicat

问题:

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What is the difference between iterator and iterable and how to use them? (13 answers)

In JavaScript ES6, what is the difference between an iterable and iterator? (2 answers)

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What is the difference between Iterator and Iterable? Is one sub-type of the other or not? What are the actual differences in some real applications?

I am trying to read some tutorials and specifications, but they are all very complicated.

(I am using ES6 and Babel, if that helps.)

回答1:

From Exploring ES6 by Dr. Axel Rauschmayer:

An iterable is a data structure that wants to make its elements accessible to the public. It does so by implementing a method whose key is Symbol.iterator. That method is a factory for iterators.

An iterator is a pointer for traversing the elements of a data structure (think cursors in databases).