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Change string URLification to avoid using the empty string, which confuses Apache no2slash()
author Adam Chlipala <adamc@hcoop.net>
date Sat, 12 Sep 2009 09:31:50 -0400
parents 0d30e6338c65
children da3ec6014d2f
line wrap: on
line source
datatype t = datatype Basis.option

fun eq [a] (_ : eq a) =
    mkEq (fn x y =>
             case (x, y) of
                 (None, None) => True
               | (Some x, Some y) => x = y
               | _ => False)

fun isSome [a] x =
    case x of
        None => False
      | Some _ => True

fun mp [a] [b] f x =
    case x of
        None => None
      | Some y => Some (f y)

fun bind [a] [b] f x =
    case x of
        None => None
      | Some y => f y