23 lines
575 B
Plaintext
23 lines
575 B
Plaintext
!import "base" !Local
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!import "list" !Local
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!import "io" !Local
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-- Mutable state via get and put.
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-- get reads the current state.
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-- put replaces the state.
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--
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-- The CLI starts with an empty (Leaf) state. This demo puts
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-- readable strings and prints them back out.
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main = io <|
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bind (put "idle") (_ :
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bind get (s1 :
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bind (putStrLn (append "state: " s1)) (_ :
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bind (put "running") (_ :
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bind get (s2 :
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bind (putStrLn (append "state: " s2)) (_ :
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bind (put "done") (_ :
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bind get (s3 :
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bind (putStrLn (append "state: " s3)) (_ :
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pure t)))))))))
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