Question

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yield statement implementation

I’ve seen msdn docs and it says:

The yield keyword signals to the compiler that the method in which it appears is an iterator block. The compiler generates a class to implement the behavior that is expressed in the iterator block. In the iterator block, the yield keyword is used together with the return keyword to provide a value to the enumerator object.

So it means yield keyword is a Syntactic sugar and compiler does the heavy work of generating the Iterator. (Am I Correct ?)

Then what is the generated implementation code for this syntactic sugar.

Answer 1

The generated code depends on the original, but generally speaking a state machine gets generated which keeps track of the current state of the collection.

See yield statement implementation, this answer by Eric Lippert and this blog post by Jon Skeet.