Implementing "Generator" support in a custom language

Posted by Roger Alsing on Stack Overflow See other posts from Stack Overflow or by Roger Alsing
Published on 2010-04-15T10:54:50Z Indexed on 2010/04/15 14:23 UTC
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generators

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yield

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dsl

I've got a bit of fettish for language design and I'm currently playing around with my own hobby language. (http://rogeralsing.com/2010/04/14/playing-with-plastic/)

One thing that really makes my mind bleed is "generators" and the "yield" keyword. I know C# uses AST transformation to transform enumerator methods into statemachines.

But how does it work in other languages? Is there any way to get generator support in a language w/o AST transformation? e.g. Does languages like Python or Ruby resort to AST transformations to solve this to?

(The question is how generators are implemented under the hood in different languages, not how to write a generator in one of them)

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