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annotate lib/ur/option.ur @ 847:0f7e2cca6d9b

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<dyn> inside <table>; fix Specialize bug with datatype decls generating other mutually-recursive datatype decls
author Adam Chlipala <adamc@hcoop.net>
date Sat, 13 Jun 2009 14:29:36 -0400
parents 0d30e6338c65
children da3ec6014d2f
rev   line source
adamc@841 1 datatype t = datatype Basis.option
adamc@841 2
adamc@846 3 fun eq [a] (_ : eq a) =
adamc@846 4 mkEq (fn x y =>
adamc@846 5 case (x, y) of
adamc@846 6 (None, None) => True
adamc@846 7 | (Some x, Some y) => x = y
adamc@846 8 | _ => False)
adamc@846 9
adamc@841 10 fun isSome [a] x =
adamc@841 11 case x of
adamc@841 12 None => False
adamc@841 13 | Some _ => True
adamc@844 14
adamc@844 15 fun mp [a] [b] f x =
adamc@844 16 case x of
adamc@844 17 None => None
adamc@844 18 | Some y => Some (f y)
adamc@846 19
adamc@846 20 fun bind [a] [b] f x =
adamc@846 21 case x of
adamc@846 22 None => None
adamc@846 23 | Some y => f y