20 lines
542 B
Plaintext
20 lines
542 B
Plaintext
-- a Maybe monad. Wraps a value like ("just", 5) or ("nothing").
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-- Bind returns ("nothing") on ("nothing"), or unwraps the value and calls the function on bind.
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return(x) -> ("just", x). -- wrap a value
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bind(("just", x), f) -> f(x). -- apply a value
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bind(("nothing"), f) -> ("nothing").
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-- equivalent to 10 * 4 + 2, but in monadic form (yay!)
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forty_two = bind(return(10), \x ->
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bind(return(x*4), \y ->
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return(y + 2)
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)
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).
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-- this will just return ("nothing")
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nothing = bind(("nothing"), \x -> x+10).
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print(forty_two).
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print(nothing).
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