Ur/Web: tests/unpoly.ur annotate

Monad.mapR3

author	Adam Chlipala <adam@chlipala.net>
date	Sat, 31 Oct 2015 11:49:30 -0400
parents	338be96f8533
children

rev	line source
adamc@1185	1 val current = return (Some "1")
adamc@1185	2 fun resolve (_ : string) = return (Some "2")
adamc@1185	3
adamc@1185	4 fun checkDeps deps =
adamc@1185	5 u <- current;
adamc@1185	6 List.foldlM (fn s (good, errs) =>
adamc@1185	7 v' <- resolve s;
adamc@1185	8 case v' of
adamc@1185	9 None =>
adamc@1185	10 return (False, <xml>
adamc@1185	11 {errs}
adamc@1185	12 Unknown library path <tt>{[s]}</tt>.<br/>
adamc@1185	13 </xml>)
adamc@1185	14 \| Some v' =>
adamc@1185	15 b <- return True;
adamc@1185	16 if b then
adamc@1185	17 return (good, errs)
adamc@1185	18 else
adamc@1185	19 return (False, <xml>
adamc@1185	20 {errs}
adamc@1185	21 Access denied to <tt>{[s]}</tt>.<br/>
adamc@1185	22 </xml>)) (True, <xml/>) deps
adamc@1185	23
adamc@1185	24 fun main () =
adamc@1185	25 p <- checkDeps ("a" :: "b" :: []);
adamc@1185	26 return <xml><body>
adamc@1185	27 {p.2}
adamc@1185	28 </body></xml>

Mercurial > urweb