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    Avoid Nested For Loops with Generators

    javascriptJavaScript

    Generators allow you to hook together multiple generators with the yield* syntax. This allows you to branch off into many different types of iterations within the main iteration and covers complex scenarios where you usually end up reaching for nested for loops.

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    Instructor: 0:00 Now because generators give us iterables and yield* can yield iterables, we can also create a second generator and yield those from another generator. For example, if I call this a shoutIterator, this can be a function, and this can take a word. Then we'll just go ahead and yield the word plus !.

    0:27 Now inside of my reverseIterator, I can yield* my shoutIterator, and we'll just pass in "hello." You'll see hello with an exclamation point. I could shout progressively louder, so 2, 3, and I can get hello and then louder, and louder, or I could combine data from my array, say something like array , then yield out array, array.

    0:55 I could do things like a with one exclamation point, louder and louder, B, and C, all because a generator gives us an iterable which a yield can loop through itself.

    1:07 You're probably thinking if you would do this traditionally you would have done nested for loops or a solution like that. Whereas with generators, you get a very easy-to-follow syntax which is very obvious what it's doing, and rather than nested for loops you're just using a function inside of a function, which is a very common and natural pattern.