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shehaaz/flip_flop.ml

Created December 12, 2013 02:14
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Fun with References: Write a function flip_flop :- unit -> (unit -> int) flip_flop: Generates a function that takes in UNIT and produces INT. Every time the generated function is called with unit it either produces "0" or "1" e.g: let ff = flip_flop();; ff();; >1 ff();; >0 ff();; >1 ...
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flip_flop.ml
let flip_flop () =
let counter = ref 0
in
fun () -> (if(!counter = 0) then counter := 1 else counter := 0; !counter);;
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shehaaz commented Dec 12, 2013

Lesson learnt:

counter (int ref) is private for every generated function. It is pretty neat

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