Streams in Common Lisp?

Section 3.5 of Str开发者_如何学Pythonucture and Interpretation of Computer Programs describes streams. Does Common Lisp have such streams built in or is there a good Common Lisp library implementing such streams?

[I mean streams in all the generality presented in section 3.5 of SICP; not just your usual i/o streams.]

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SERIES is a featureful library providing that sort of functionality. For a shorter and more readable example of how the concept of streams maps to Common Lisp, see Pipes.