Ur/Web: demo/listFun.ur annotate

Saving paper decisions

author	Adam Chlipala <adamc@hcoop.net>
date	Sat, 07 Nov 2009 11:06:38 -0500
parents	7ef4b2911b09
children

rev	line source
adamc@398	1 open List
adamc@398	2
adamc@386	3 functor Make(M : sig
adamc@386	4 type t
adamc@398	5 val toString : t -> string
adamc@398	6 val fromString : string -> option t
adamc@386	7 end) = struct
adamc@398	8 fun toXml (ls : list M.t) =
adamc@398	9 case ls of
adamc@398	10 Nil => <xml>[]</xml>
adamc@398	11 \| Cons (x, ls') => <xml>{[M.toString x]} :: {toXml ls'}</xml>
adamc@398	12
adamc@501	13 fun console (ls : list M.t) =
adamc@501	14 let
adamc@501	15 fun cons (r : {X : string}) =
adamc@501	16 case M.fromString r.X of
adamc@501	17 None => return <xml><body>Invalid string!</body></xml>
adamc@501	18 \| Some v => console (Cons (v, ls))
adamc@501	19 in
adamc@501	20 return <xml><body>
adamc@501	21 Current list: {toXml ls}<br/>
adamc@501	22 Reversed list: {toXml (rev ls)}<br/>
adamc@501	23 Length: {[length ls]}<br/>
adamc@501	24 <br/>
adamc@398	25
adamc@501	26 <form>
adamc@501	27 Add element: <textbox{#X}/> <submit action={cons}/>
adamc@501	28 </form>
adamc@501	29 </body></xml>
adamc@501	30 end
adamc@398	31
adamc@398	32 fun main () = console Nil
adamc@386	33 end

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