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view lib/ur/option.urs @ 1240:beb67ff4c8a0

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'also' policies and policy reduction; calendar in good shape
author Adam Chlipala <adamc@hcoop.net>
date Thu, 15 Apr 2010 10:00:30 -0400
parents 757dbac0454d
children a99b743a3087
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datatype t = datatype Basis.option

val eq : a ::: Type -> eq a -> eq (t a)
val ord : a ::: Type -> ord a -> ord (t a)

val isNone : a ::: Type -> t a -> bool
val isSome : a ::: Type -> t a -> bool

val mp : a ::: Type -> b ::: Type -> (a -> b) -> t a -> t b
val bind : a ::: Type -> b ::: Type -> (a -> option b) -> t a -> t b

val get : a ::: Type -> a -> option a -> a