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47 lines
920 B
Plaintext
47 lines
920 B
Plaintext
-- This confusingly gives an error that
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-- it doesn't know what `Console.simulate` is.
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effect State s where
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get : {State s} s
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set : s -> {State s} ()
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effect Console where
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read : {Console} (Optional Text)
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write : Text -> {Console} ()
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use Console simulate
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fst x = case x of Pair.Pair a _ -> a
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snd x = case x of Pair.Pair _ (Pair.Pair b _) -> b
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namespace Console where
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simulate : Effect Console a -> {State ([Text], [Text])} a
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simulate c = case c of
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{Console.read -> k} ->
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io = State.get
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ins = fst io
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outs = snd io
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State.set (drop 1 ins, outs)
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todo
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{Console.write t -> k} ->
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io = State.get
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ins = fst io
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outs = snd io
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todo
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(++) = concatenate
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handle simulate in
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use Console read write
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use Optional Some None
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write "What's your name?"
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case read of
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Some name -> write ("Hello" ++ name)
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None -> write "Fine, be that way."
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()
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